Flag Description Default Current value Experimental
catalog_max_lock_skipped_topic_updates (int32) Maximum number of topic updates skipped for a table due to lock contention in catalogd after which it mustbe added to the topic the update log. This limit only applies to distinct lock operations which block the topic update thread. 3 3 false
catalog_operation_log_size (int32) Number of catalog operation log records to retain in catalogd. If -1, the operation log has unbounded size. 100 100 false
catalog_service_port (int32) port where the CatalogService is running 26000 26000 false
catalog_topic_mode (string) The type of data that the catalog service will publish into the Catalog StateStore topic. Valid values are 'full', 'mixed', or 'minimal'. In 'full' mode, complete catalog objects are published any time a new version is available. In 'minimal' mode, only a minimal object is published when a new version of a catalog object is available. In 'mixed' mode, both types of topic entries are published. When all impalad coordinators are configured with --use_local_catalog disabled (the default), 'full' mode should be used. If all impalad coordinators are configured with --use_local_catalog enabled, 'minimal' mode should be used. When some impalads are configured with --use_local_catalog disabled and others configured with it enabled, then 'mixed' mode is required. full minimal false
common_hms_event_types (string) Common HMS event types that will be used in eventTypeSkipList when fetching events from HMS. The strings come from constants in org.apache.hadoop.hive.metastore.messaging.MessageBuilder. When bumping Hive versions, the list might need to be updated accordingly. To avoid bringing too much computation overhead to HMS's underlying RDBMS in evaluating predicates of EVENT_TYPE != 'xxx', rare event types are not tracked in this list. They are CREATE_FUNCTION,DROP_FUNCTION,ADD_PRIMARYKEY,ADD_FOREIGNKEY,ADD_UNIQUECONSTRAINT,ADD_NOTNULLCONSTRAINT, ADD_DEFAULTCONSTRAINT, ADD_CHECKCONSTRAINT, DROP_CONSTRAINT,CREATE_ISCHEMA, ALTER_ISCHEMA, DROP_ISCHEMA, ADD_SCHEMA_VERSION,ALTER_SCHEMA_VERSION, DROP_SCHEMA_VERSION, CREATE_CATALOG, ALTER_CATALOG,DROP_CATALOG, CREATE_DATACONNECTOR, ALTER_DATACONNECTOR, DROP_DATACONNECTOR. ADD_PARTITION,ALTER_PARTITION,DROP_PARTITION,ADD_PARTITION,ALTER_PARTITION,DROP_PARTITION,CREATE_TABLE,ALTER_TABLE,DROP_TABLE,CREATE_DATABASE,ALTER_DATABASE,DROP_DATABASE,INSERT,OPEN_TXN,COMMIT_TXN,ABORT_TXN,ALLOC_WRITE_ID_EVENT,ACID_WRITE_EVENT,BATCH_ACID_WRITE_EVENT,UPDATE_TBL_COL_STAT_EVENT,DELETE_TBL_COL_STAT_EVENT,UPDATE_PART_COL_STAT_EVENT,UPDATE_PART_COL_STAT_EVENT_BATCH,DELETE_PART_COL_STAT_EVENT,COMMIT_COMPACTION_EVENT,RELOAD ADD_PARTITION,ALTER_PARTITION,DROP_PARTITION,ADD_PARTITION,ALTER_PARTITION,DROP_PARTITION,CREATE_TABLE,ALTER_TABLE,DROP_TABLE,CREATE_DATABASE,ALTER_DATABASE,DROP_DATABASE,INSERT,OPEN_TXN,COMMIT_TXN,ABORT_TXN,ALLOC_WRITE_ID_EVENT,ACID_WRITE_EVENT,BATCH_ACID_WRITE_EVENT,UPDATE_TBL_COL_STAT_EVENT,DELETE_TBL_COL_STAT_EVENT,UPDATE_PART_COL_STAT_EVENT,UPDATE_PART_COL_STAT_EVENT_BATCH,DELETE_PART_COL_STAT_EVENT,COMMIT_COMPACTION_EVENT,RELOAD false
default_skipped_hms_event_types (string) HMS event types that are not used by Impala. They are skipped by default in fetching HMS event batches. Only in few places they will be fetched, e.g. fetching the latest event time in HMS. OPEN_TXN,UPDATE_TBL_COL_STAT_EVENT,UPDATE_PART_COL_STAT_EVENT OPEN_TXN,UPDATE_TBL_COL_STAT_EVENT,UPDATE_PART_COL_STAT_EVENT false
enable_reload_events (bool) This configuration is used to fire a refresh/invalidate table event to the HMS such that other event processors (such as other Impala catalogds) that poll HMS notification logs can process this event. The default value is false, so impala will not fire this event. If enabled, impala will fire this event and other catalogD will process it.This config only affects the firing of the reload event. Processing of reload event will always happen false false false
enable_skipping_older_events (bool) This configuration is used to skip anyolder events in the event processor based on the lastRefreshEventId on thedatabase/table/partition in the cache. All the DML queries that change the metadatain the catalogD's cache will update the lastRefreshEventId i.e.., fetch the latestavailable event on HMS and set it on the object. In case the event processor islagging, the older events in event processor queue can be skipped by comparing thecurrent event id to that of lastRefreshEventId. The default is set to false todisable the optimisation. Set this true to enable skipping the older events andquickly catch with the events of HMS false false false
enable_sync_to_latest_event_on_ddls (bool) This configuration is used to sync db/table in catalogd cache to latest HMS event id whenever DDL operations are performed from Impala shell and catalog metastore server (if enabled). If this config is enabled, then the flag invalidate_hms_cache_on_ddls should be disabled false false false
fallback_to_hms_on_errors (bool) This configuration is only used if start_hms_server is true. This is used to determine if the Catalog should fallback to the backing HMS service if there are errors while processing the HMS request true true false
file_metadata_reload_properties (string) This configuration is used to whitelist the table properties that are supposed torefresh file metadata when these properties are changed. To skip this optimization,set the value to empty string EXTERNAL, metadata_location,transactional, transactional_properties, TRANSLATED_TO_EXTERNAL, repl.last.id EXTERNAL, metadata_location,transactional, transactional_properties, TRANSLATED_TO_EXTERNAL, repl.last.id false
hms_event_incremental_refresh_transactional_table (bool) When set to true events processor will refresh transactional tables incrementally for partition level events. Otherwise, it will always reload the whole table for transactional tables. true true false
hms_port (int32) If start_hms_server is set to true, this configuration specifies the port number at which it is started. 5899 5899 false
invalidate_global_metadata_on_event_processing_failure (bool) This configuration is used to global invalidate metadata when invalidate_metadata_on_event_processing_failure cannot invalidate metadata for table(s). The default value is false. When enabled, global invalidate metadata is performed automatically. Otherwise, failure can put metastore event processor in non-active state. false false false
invalidate_hms_cache_on_ddls (bool) This configuration is used only if start_hms_server is true. This is used to invalidate catalogd cache for non transactional tables if alter/create/delete table hms apis are invoked over catalogd's metastore endpoint true true false
invalidate_metadata_on_event_processing_failure (bool) This configuration is used to invalidate metadata for table(s) upon event process failure other than HMS connection issues. The default value is true. When enabled, invalidate metadata is performed automatically upon event process failure. Otherwise, failure can put metastore event processor in non-active state. true true false
max_wait_time_for_sync_ddl_s (int32) Maximum time (in seconds) until which a sync ddl operation will wait for the updated tables to be the added to the catalog topic. A value of 0 means sync ddl operation will wait as long as necessary until the update is propogated to all the coordinators. This flag only takes effect when topic_update_tbl_max_wait_time_ms is enabled.A value greater than 0 means catalogd will wait until that number of seconds before throwing an error indicating that not all the coordinators might have applied the changes caused due to the ddl. 0 0 false
start_hms_server (bool) When set to true catalog server starts a HMS server at a port specified by hms_port flag false false false
topic_update_log_gc_frequency (int32) Frequency at which the entries of the catalog topic update log are garbage collected. An entry may survive for (2 * TOPIC_UPDATE_LOG_GC_FREQUENCY) - 1 topic updates. 1000 1000 false
topic_update_tbl_max_wait_time_ms (int64) Maximum time (in milliseconds) catalog's topic update thread will wait to acquire lock on table. If the topic update thread cannot acquire a table lock it skips the table from that topic update and processes the table in the next update. However to prevent starvation it only skips the table catalog_max_lock_skipped_topic_updates many times. After that limit is hit, topic thread block until it acquires the table lock. A value of 0 disables the timeout based locking which means topic update thread will always block until table lock is acquired. 120000 120000 false
initial_hms_cnxn_timeout_s (int32) Number of seconds catalogd will wait to establish an initial connection to the HMS before exiting. 120 120 false
load_catalog_in_background (bool) If true, loads catalog metadata in the background. If false, metadata is loaded lazily (on access). false false false
max_hdfs_partitions_parallel_load (int32) (Advanced) Number of threads used to load block metadata for HDFS based partitioned tables. Due to HDFS architectural limitations, it is unlikely to get a linear speed up beyond 5 threads. 5 5 false
max_nonhdfs_partitions_parallel_load (int32) (Advanced) Number of threads used to load block metadata for tables that do not support the notion of blocks/storage IDs. Currently supported for S3/ADLS. 20 20 false
num_metadata_loading_threads (int32) (Advanced) The number of metadata loading threads (degree of parallelism) to use when loading catalog metadata. 16 16 false
asm_module_dir (string) if set, saves disassembly for generated IR modules to the specified directory. false
disable_optimization_passes (bool) if true, disables llvm optimization passes (used for testing) false false false
dump_ir (bool) if true, output IR after optimization passes false false false
opt_module_dir (string) if set, saves optimized generated IR modules to the specified directory. false
perf_map (bool) if true, generate /tmp/perf-<pid>.map file for linux perf symbols. This is not recommended for production use because it may affect performance. false false false
print_llvm_ir_instruction_count (bool) if true, prints the instruction counts of all JIT'd functions false false false
unopt_module_dir (string) if set, saves unoptimized generated IR modules to the specified directory. false
abort_on_config_error (bool) Abort Impala startup if there are improper configs or running on unsupported hardware. true true false
active_catalogd_designation_monitoring_interval_ms (int64) (Advanced) Interval (in ms) with which the statestore monitors if active catalogd is designated. 100 100 false
anonymous_user_name (string) Default username used when a client connects to an unsecured impala daemon and does not specify a username. anonymous anonymous false
be_principal (string) Kerberos principal for backend network connections only,overriding --principal if set. Must not be set if --principal is not set. false
blacklisted_dbs (string) Comma separated list for blacklisted databases. Configure which databases to be skipped for loading (in startup and global INVALIDATE METADATA). Users can't access, create, or drop databases which are blacklisted. sys,information_schema sys,information_schema false
blacklisted_tables (string) Comma separated full names (in format: <db>.<table>) of blacklisted tables. Configure which tables to be skipped for loading (in startup and reseting metadata of the table). Users can't access, create, or drop tables which are blacklisted false
buffer_pool_clean_pages_limit (string) (Advanced) Limit on bytes of clean pages that will be accumulated in the buffer pool. Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of the buffer pool limit ('<int>%'). Defaults to bytes if no unit is given.. 10% 10% false
buffer_pool_limit (string) (Advanced) Limit on buffer pool size. Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of the process memory limit (minus the JVM heap if --mem_limit_includes_jvm is true) ('<int>%'). Defaults to bytes if no unit is given. The default value and behaviour of this flag may change between releases. 85% 85% false
catalogd_ha_preemption_wait_period_ms (int64) (Advanced) The time after which statestore designates the first registered catalogd as active if statestore does not receive registration request from the second catalogd. 10000 10000 false
compact_catalog_topic (bool) If true, catalog updates sent via the statestore are compacted before transmission. This saves network bandwidth at the cost of a small quantity of CPU time. Enable this option in cluster with large catalogs. It must be enabled on both the catalog service, and all Impala demons. true true false
debug_actions (string) For testing only. Uses the same format as the debug action query options, but allows for injection of debug actions in code paths where query options are not available. false
delete_hadoop_s3_dir_markers (bool) Has effect only when using AWS SDK for S3 (enable_aws_lib=true + USE_AWS_WRITER=true)If Hive and other components Hadoop version supports fs.s3a.directory.marker.retention=keep set delete_hadoop_s3_dir_markers=false and fs.s3a.directory.marker.retention=keep.Otherwise, set delete_hadoop_s3_dir_markers=true.Additional details on Hadoop directory markers can be found at https://hadoop.apache.org/docs/stable/hadoop-aws/tools/hadoop-aws/directory_markers.html true true false
disable_kudu (bool) If true, Kudu features will be disabled. false false false
enable_aws_lib (bool) Enables possibility for use AWS SDK in read/write operations to S3.If set to false, the AWS SDK will not be used and the Hadoop FileSystem implementation will be used instead.If set to true use USE_AWS_WRITER, USE_AWS_READER query options to enable AWS SDK for read/write operations specifically.If set to false USE_AWS_WRITER, USE_AWS_READER query options will have no effect. false false false
enable_catalogd_ha (bool) Set to true to enable CatalogD HA false false false
enable_catalogd_hms_cache (bool) If true, response for the HMS APIs that are implemented in catalogd will be served from catalogd. If this flag is false or a given API is not implemented in catalogd, it will be redirected to HMS. true true false
enable_incremental_metadata_updates (bool) If true, Catalog Server will send incremental table updates in partition level in the statestore topic updates. Legacy coordinators will apply the partition updates incrementally, i.e. reuse unchanged partition metadata. Disable this feature by setting this to false in the Catalog Server. Then metadata of each table will be propagated as a whole object in the statestore topic updates. Note that legacy coordinators can apply incremental or full table updates so don't need this flag. true true false
enable_insert_events (bool) Enables insert events in the events processor. When this configuration is set to true Impala will generate INSERT event types which when received by other Impala clusters can be used to automatically refresh the tables or partitions. Event processing must be turned on for this flag to have any effect. true true false
enable_legacy_avx_support (bool) If true, Impala relaxes its x86_64 CPU feature requirement to allow running on machines with AVX but no AVX2. This allows running Impala on older machines without AVX2 support. This is a legacy mode that will be removed in a future release. false false false
enable_minidumps (bool) Whether to enable minidump generation upon process crash or SIGUSR1. true true false
enable_process_lifetime_heap_profiling (bool) (Advanced) Enables heap profiling for the lifetime of the process. Profile output will be stored in the directory specified by -heap_profile_dir. Enabling this option will disable the on-demand/remote server profile handlers. false false false
enable_stats_extrapolation (bool) If true, uses table statistics computed with COMPUTE STATS to extrapolate the row counts of partitions. false false false
force_catalogd_active (bool) Set to true to force this catalogd instance to take active role. It's used to perform manual fail over for catalog service. false false false
geospatial_library (string) Specifies which implementation of geospatial functions should be included as builtins. Possible values: ["NONE", "HIVE_ESRI"] NONE NONE false
heap_profile_dir (string) Output directory to store heap profiles. If not set profiles are stored in the current working directory. false
hms_event_polling_interval_s (int32) Configure catalogd to refresh cached table metadata based on metastore events. These metastore events could be generated by external systems like Apache Hive or a different Impala cluster using the same Hive metastore server as this one. A non-zero value of this flag sets the polling interval of catalogd in seconds to fetch new metastore events. A value of zero disables this feature. When enabled, this flag has the same effect as "REFRESH" statement on the table for certain metastore event types. Additionally, in case of events which detect creation or removal of objects from metastore, catalogd adds or removes such objects from its cached metadata. This feature is independent of time and memory based automatic invalidation of tables. 1 1 false
hostname (string) Hostname to use for this daemon, also used as part of the Kerberos principal, if enabled. If not set, the system default will be used impala-0.impala-sv.impala-flight-sql.svc.cluster.local false
iceberg_allow_datafiles_in_table_location_only (bool) If true, Impala does not allow Iceberg data file locations outside of the table directory during reads true true false
iceberg_reload_new_files_threshold (int32) (Advanced) If during a table refresh the number of new files are greater than this, catalogd will completely reload all file metadata. If number of new files are less or equal to this, catalogd will only load the metadata of the newly added files. 100 100 false
impala_slow_rpc_threshold_ms (int64) (Advanced) Threshold for considering Impala internal RPCs to be unusually slow. Slow RPCs trigger additional logging and other diagnostics. Lowering this value may result in false positivesThis overrides KRPC's --rpc_duration_too_long_ms setting. 120000 120000 false
inc_stats_size_limit_bytes (int64) Maximum size of incremental stats the catalog is allowed to serialize per table. This limit is set as a safety check, to prevent the JVM from hitting a maximum array limit of 1GB (or OOM) while building the thrift objects to send to impalads. By default, it's set to 200MB 209715200 209715200 false
invalidate_tables_on_memory_pressure (bool) Configure catalogd to invalidate recently unused tables when the old GC generation is almost full. This is independent from time-based invalidation configured by invalidate_table_timeout_s. To enable this feature, a true flag must be applied to both catalogd and impalad. false false false
invalidate_tables_timeout_s (int32) If a table has not been referenced in a SQL statement for more than the configured amount of time, the catalog server will automatically evict its cached metadata about this table. This has the same effect as a user-initiated "INVALIDATE METADATA" statement on the table. Configuring this to 0 disables time-based automatic invalidation of tables. This is independent from memory-based invalidation configured by invalidate_tables_on_memory_pressure. To enable this feature, a non-zero flag must be applied to both catalogd and impalad. 0 0 false
keytab_file (string) Absolute path to Kerberos keytab file false
krb5_ccname (string) Absolute path to the file based credentials cache that we pass to the KRB5CCNAME environment variable. /tmp/krb5cc_impala_internal /tmp/krb5cc_impala_internal false
krb5_conf (string) Absolute path to Kerberos krb5.conf if in a non-standard location. Does not normally need to be set. false
krb5_debug_file (string) Turn on Kerberos debugging and output to this file false
krpc_port (int32) port on which KRPC based ImpalaInternalService is exported 27000 27000 false
kudu_client_connection_negotiation_timeout_ms (int32) (Advanced) Timeout for connection negotiation between Kudu client and Kudu masters and tablet servers, in milliseconds 3000 3000 false
kudu_client_rpc_timeout_ms (int32) (Advanced) Timeout (milliseconds) set for individual Kudu client rpcs. An operation may consist of several rpcs, so this is expected to be less than kudu_operation_timeout_ms. This must be a positive value or it will be ignored and Kudu's default of 10s will be used. There is no way to disable timeouts. 0 0 false
kudu_operation_timeout_ms (int32) Timeout (milliseconds) set for all Kudu operations. This must be a positive value, and there is no way to disable timeouts. 180000 180000 false
kudu_sasl_protocol_name (string) SASL protocol name for Kudu kudu kudu false
load_auth_to_local_rules (bool) If true, load auth_to_local configuration from hdfs' core-site.xml. When enabled, impalad reads the rules from the property hadoop.security.auth_to_local and applies them to translate the Kerberos principal to its corresponding local user name for authorization. false false false
log_filename (string) Prefix of log filename - full path is <log_dir>/<log_filename>.[INFO|WARN|ERROR|FATAL] impalad false
log_rotation_match_pid (bool) If set to True, Impala log rotation will only consider log files that match with PID of currently running service. Otherwise, log rotation will ignore the PID in log file names and may remove older log files from previous PID run. Set to True if log files from prior run must be retained or when running multiple instances of same service with common log directory. Default to False. false false false
max_log_files (int32) Maximum number of log files to retain per severity level. The most recent log files are retained. If set to 0, all log files are retained. 10 2 false
max_minidumps (int32) Maximum number of minidump files to keep per daemon. Older files are removed first. Set to 0 to keep all minidump files. 9 9 false
mem_limit (string) Limit on process memory consumption. Includes the JVM's memory consumption only if --mem_limit_includes_jvm is true. Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of the physical memory ('<int>%'). Defaults to bytes if no unit is given. 80% 1825361101 false
mem_limit_includes_jvm (bool) If true, --mem_limit will include the JVM's max heap size and committed memory in the process memory limit. false false false
min_buffer_size (int64) (Advanced) The minimum buffer size to use in the buffer pool 8192 8192 false
min_privilege_set_for_show_stmts (string) Comma separated list of privileges. Any one of them is required to show a database or table. Defaults to "any" which means if the user has any privilege (CREATE, SELECT, INSERT, etc) on a database or table, the database/table is visible in the results of SHOW DATABASES/TABLES. If set to "select", only dbs/tables on which the user has SELECT privilege will be shown. If set to "select,insert", only dbs/tables on which the user has SELECT or INSERT privilege will be shown. In practice, this flag can be set to "select" or "select,insert" to improve performance of SHOW DATABASES/TABLES and GET_SCHEMAS/GET_TABLES, especially when using Sentry and having thousands of candidate dbs/tables to be checked with a user with large scale of privileges. No significant performance gain when using Ranger any any false
minidump_path (string) Directory to write minidump files to. This can be either an absolute path or a path relative to log_dir. Each daemon will create an additional sub-directory to prevent naming conflicts and to make it easier to identify a crashing daemon. Minidump files contain crash-related information in a compressed format and will be written when a daemon exits unexpectedly, for example on an unhandled exception or signal. It is also possible to create minidumps on demand without exiting the process by sending SIGUSR1. Set to empty to disable writing minidump files. minidumps /opt/minidumps/impalad false
minidump_size_limit_hint_kb (int32) Size limit hint for minidump files in KB. If a minidump exceeds this value, then breakpad will reduce the stack memory it collects for each thread from 8KB to 2KB. However it will always include the full stack memory for the first 20 threads, including the thread that crashed. 20480 102400 false
num_check_authorization_threads (int32) The number of threads used to check authorization for the user when executing show tables/databases. This configuration is applicable only when authorization is enabled. A value of 1 disables multi-threaded execution for checking authorization.However, a small value of larger than 1 may limit the parallism of FE requests when checking authorization with a high concurrency. The value must be in the range of 1 to 128. 1 1 false
principal (string) Kerberos principal. If set, both client and backend network connections will use Kerberos encryption and authentication and the daemon will acquire a Kerberos TGT (i.e. do the equivalent of the kinit command) and keep it refreshed for the lifetime of the daemon. If this is not set the TGT ticket will not be acquired and incoming connections will not be authenticated or encrypted using Kerberos. However, the TGT and other settings may be inherited from the environment and used by client libraries in certain cases. false
pull_table_types_and_comments (bool) When set, catalogd will always load the table types and comments at startup and in executing INVALIDATE METADATA commands. In other words, unloaded tables will not just contain the table names, but also the table types and comments. This is a catalogd-only flag. Required if users want GET_TABLES requests return correct table types or comments. false false false
re2_mem_limit (string) Maximum bytes of memory to be used by re2's regex engine to hold the compiled form of the regexp. For more memory-consuming patterns, this can be set to be a higher number.Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of memory limit for RE2 max_mem opt ('<int>%'). Defaults to bytes if no unit is given.Default to 8MB. Using percentage is discouraged. 8MB 8MB false
read_size (int32) (Advanced) The preferred I/O request size in bytes to issue to HDFS or the local filesystem. Increasing the read size will increase memory requirements. Decreasing the read size may decrease I/O throughput. 8388608 8388608 false
redaction_rules_file (string) Absolute path to sensitive data redaction rules. The rules will be applied to all log messages and query text shown in the Web UI and audit records. Query results will not be affected. Refer to the documentation for the rule file format. false
redirect_stdout_stderr (bool) If true, redirects stdout/stderr to INFO/ERROR log. true true false
reserved_words_version (string) Reserved words compatibility version. Reserved words cannot be used as identifiers in SQL. This flag determines the impala version from which the reserved word list is taken. The value must be one of ["2.11.0", "3.0.0"]. 3.0.0 3.0.0 false
skip_external_kerberos_auth (bool) (Advanced) skip kerberos authentication for incoming external connections to this daemon, e.g. clients connecting to the HS2 interface. Only has an effect if --principal is set, i.e. Kerberos is enabled. false false false
skip_internal_kerberos_auth (bool) (Advanced) skip kerberos authentication for incoming internal connections from other daemons within the Impala cluster (i.e. impalads, statestored, catalogd). Must be set to the same value across all daemons. Only has an effect if --principal is set, i.e. Kerberos is enabled. false false false
spnego_keytab_file (string) Absolute path to Kerberos keytab file for HTTP spnego. If it is empty, --keytab_file flag will be used. false
state_store_2_host (string) hostname where second StatestoreService instance is running localhost localhost false
state_store_2_port (int32) port where second StatestoreService instance is running 24001 24001 false
state_store_ha_port (int32) port where StatestoreHaService is running 24020 24020 false
state_store_host (string) hostname where StatestoreService is running localhost statestore-0.statestore-sv false
state_store_port (int32) port where StatestoreService is running 24000 24000 false
tcmalloc_max_total_thread_cache_bytes (int64) (Advanced) Bound on the total amount of bytes allocated to TCMalloc thread caches. If left at 0 (default), use the default value in TCMalloc library. 0 1073741824 false
tolerate_statestore_startup_delay (bool) If set to true, the subscriber is able to tolerate the delay of the statestore's availability. The subscriber's process will not exit if it cannot register with the specified statestore on startup. But instead it enters into Recovery mode, it will loop, sleep and retry till it successfully registers with the statestore. true true false
unlock_zorder_sort (bool) If true, enables using ZORDER option for SORT BY. true true false
update_catalogd_rpc_resend_interval_ms (int64) (Advanced) Interval (in ms) with which the statestore resends the update catalogd RPC to a subscriber if the statestore has failed to send the RPC to the subscriber. 100 100 false
use_resolved_hostname (bool) If true, --hostname is resolved before use, so that the IP address will be used everywhere instead of the hostname. false false false
use_subscriber_id_as_catalogd_priority (bool) Subscriber-id is used as priority value of catalogd instance if this is set as true. Otherwise, registration_id which is generated as random number will be used as priority value of catalogd instance. false false false
jvm_automatic_add_opens (bool) Adds necessary --add-opens options for core Java modules necessary to correctly calculate catalog metadata cache object sizes. true true false
local_library_dir (string) Scratch space for local fs operations. Currently used for copying UDF binaries locally from HDFS and also for initializing the timezone db /tmp /opt/impala/udf false
memory_maintenance_sleep_time_ms (int32) Sleep time in milliseconds between memory maintenance iterations 10000 10000 false
pause_monitor_sleep_time_ms (int64) Sleep time in milliseconds for pause monitor thread. 500 500 false
pause_monitor_warn_threshold_ms (int64) If the pause monitor sleeps more than this time period, a warning is logged. If set to 0 or less, pause monitor is disabled. 10000 10000 false
data_source_batch_size (int32) Batch size for calls to GetNext() on external data sources. 1024 1024 false
exchg_node_buffer_size_bytes (int64) (Advanced) Maximum size of per-query receive-side buffer 10485760 10485760 false
enable_quadratic_probing (bool) Enable quadratic probing hash table true true false
always_use_data_cache (bool) (Advanced) Always uses the IO data cache for all reads, regardless of whether the read is local or remote. By default, the IO data cache is only used if the data is expected to be remote. Used by tests. false false false
max_row_batches (int32) the maximum number of batches to queue in multithreaded HDFS scans 0 0 false
min_filter_reject_ratio (double) (Advanced) If the percentage of rows rejected by a runtime filter drops below this value, the filter is disabled. 0.10000000000000001 0.10000000000000001 false
enable_json_scanner (bool) If set false, disable reading from json format tables. true true false
kudu_max_row_batches (int32) The maximum size of the row batch queue, for Kudu scanners. 0 0 false
kudu_read_mode (string) (Advanced) Sets the Kudu scan ReadMode. Supported Kudu read modes are READ_LATEST and READ_AT_SNAPSHOT. Can be overridden with the query option of the same name. READ_LATEST READ_LATEST false
kudu_scanner_keep_alive_period_sec (int32) The period at which Kudu Scanners should send keep-alive requests to the tablet server to ensure that scanners do not time out. 15 15 false
kudu_error_buffer_size (int32) The size (bytes) of the Kudu client buffer for returning errors, with a min of 1KB.If the actual errors exceed this size the query will fail. 10485760 10485760 false
kudu_ignore_conflicts (bool) Control whether Impala should ignore Kudu conflict error on duplicate and absent primary keys during write operations. If this flag is set to true and Kudu cluster supports ignore operations, Impala will use {INSERT,UPDATE,DELETE}_IGNORE operations of Kudu API. Otherwise, Impala will use regular {INSERT,UPDATE,DELETE} operations and logs any occurrences of such conflict error. See also kudu_ignore_conflicts_in_transaction flag. true true false
kudu_ignore_conflicts_in_transaction (bool) Control whether Kudu transaction should ignore conflict error on duplicate and absent primary keys during write operations. If set to true, the Kudu transaction will not be aborted for hitting such a conflict error. This flag is only considered if kudu_ignore_conflicts flag is true. false false false
kudu_mutation_buffer_size (int32) The size (bytes) of the Kudu client buffer for mutations. 10485760 10485760 false
kudu_client_num_reactor_threads (int32) Number of threads the Kudu client can use to send rpcs to Kudu. Must be > 0. 4 4 false
kudu_client_v (int32) If >= 0, used to set the verbose logging level on the Kudu client instead of using the value of -v -1 -1 false
max_page_header_size (int32) max parquet page header size in bytes 8388608 8388608 false
max_queued_row_batch_bytes (int64) (Advanced) the maximum bytes of queued rows per multithreaded scan node. 16777216 16777216 false
runtime_filter_wait_time_ms (int32) (Advanced) the maximum time, in ms, that a scan node will wait for expected runtime filters to arrive. 1000 1000 false
enabled_hdfs_text_scanner_plugins (string) (Advanced) whitelist of HDFS text scanner plugins that Impala will try to dynamically load. Must be a comma-separated list of upper-case compression codec names. Each plugin implements support for decompression and hands off the decompressed bytes to Impala's builtin text parser for further processing (e.g. parsing delimited text). false
partitioned_topn_in_mem_partitions_limit (int32) (Experimental) Soft limit on the number of in-memory partitions in an instance of the partitioned top-n operator. 1000 1000 false
partitioned_topn_soft_limit_bytes (int64) (Experimental) Soft limit on the number of in-memory partitions in an instance of the partitioned top-n operator. 67108864 67108864 false
ai_api_key_jceks_secret (string) The jceks secret key used for extracting the api key from configured keystores. 'hadoop.security.credential.provider.path' in core-site must be configured to include the keystore storing the corresponding secret. <redacted> false
ai_connection_timeout_s (int32) (Advanced) The time in seconds for connection timed out when communicating with an external AI engine 10 10 false
ai_endpoint (string) The default API endpoint for an external AI engine. https://api.openai.com/v1/chat/completions https://api.openai.com/v1/chat/completions false
ai_model (string) The default AI model used by an external AI engine. gpt-4 gpt-4 false
hdfs_zone_alias_conf (string) HDFS/S3A/ADLS path to config file defining non-standard time-zone aliases. false
hdfs_zone_info_zip (string) HDFS/S3A/ADLS path to a zip archive of the IANA time-zone database to use. false
rpc_acceptor_listen_backlog (int32) Socket backlog parameter used when listening for RPC connections. This defines the maximum length to which the queue of pending TCP connections inbound to the RPC server may grow. If a connection request arrives when the queue is full, the client may receive an error. Higher values may help the server ride over bursts of new inbound connection requests. 128 128 false
rpc_encrypt_loopback_connections (bool) Whether to encrypt data transfer on RPC connections that stay within a single host. Encryption here is likely to offer no additional security benefit since only a local 'root' user could intercept the traffic, and wire encryption does not suitably protect against such an attacker. false false false
rpc_negotiation_inject_delay_ms (int32) If enabled, injects the given number of milliseconds delay into the RPC negotiation process on the server side. 0 0 false
rpc_trace_negotiation (bool) If enabled, dump traces of all RPC negotiations to the log false false false
rpc_callback_max_cycles (int64) The maximum number of cycles for which an RPC callback should be allowed to run without emitting a warning. (Advanced debugging option) 100000000 100000000 false
rpc_inject_cancellation_state (int32) If this flag is not -1, it is the state in which a cancellation request will be injected. Should use values in OutboundCall::State only -1 -1 false
rpc_reopen_outbound_connections (bool) Open a new connection to the server for every RPC call. If not enabled, an already existing connection to a server is reused upon making another call to the same server. When this flag is enabled, an already existing _idle_ connection to the server is closed upon making another RPC call which would reuse the connection otherwise. Used by tests only. false false false
tcp_keepalive_probe_period_s (int32) The duration in seconds after an outbound connection has gone idle before a TCP keepalive probe is sent to the peer. Set to 0 to disable TCP keepalive probes from being sent. 60 60 false
tcp_keepalive_retry_count (int32) The maximum number of keepalive probes sent before declaring the remote end as dead. Effective only if --tcp_keepalive_probe_period_s is not 0. 10 10 false
tcp_keepalive_retry_period_s (int32) The duration in seconds between successive keepalive probes from an outbound connection if the previous probes are not acknowledged. Effective only if --tcp_keepalive_probe_period_s is not 0. 3 3 false
remember_clients_ttl_ms (int64) Maximum amount of time, in milliseconds, the server "remembers" a client for the purpose of caching its responses. After this period without hearing from it, the client is no longer remembered and the memory occupied by its responses is reclaimed. Retries of requests older than 'remember_clients_ttl_ms' are treated as new ones. 3600000 3600000 false
remember_responses_ttl_ms (int64) Maximum amount of time, in milliseconds, the server "remembers" a response to a specific request for a client. After this period has elapsed, the response may have been garbage collected and the client might get a response indicating the request is STALE. 600000 600000 false
result_tracker_gc_interval_ms (int64) Interval at which the result tracker will look for entries to GC. 1000 1000 false
rpc_dump_all_traces (bool) If true, dump all RPC traces at INFO level false false false
rpc_duration_too_long_ms (int32) Threshold (in milliseconds) above which a RPC is considered too long and its duration and method name are logged at INFO level. The time measured is between when a RPC is accepted and when its call handler completes. 1000 120000 false
rpc_inject_invalid_authn_token_ratio (double) If set higher than 0, AuthenticateByToken() randomly injects errors replying with FATAL_INVALID_AUTHENTICATION_TOKEN code. The flag's value corresponds to the probability of the fault injection event. Used for only for tests. 0 0 false
rpc_inject_invalid_channel_bindings_ratio (double) The ratio of injection of invalid channel bindings during connection negotiation. This is a test-only flag. 0 0 false
rpc_send_channel_bindings (bool) Whether to send channel bindings in NegotiatePB response as prescribed by RFC 5929. This is a test-only flag. true true false
trusted_subnets (string) A trusted subnet whitelist. If set explicitly, all unauthenticated or unencrypted connections are prohibited except the ones from the specified address blocks. Otherwise, private network (127.0.0.0/8, etc.) and local subnets of all local network interfaces will be used. Set it to '0.0.0.0/0' to allow unauthenticated/unencrypted connections from all remote IP addresses. However, if network access is not otherwise restricted by a firewall, malicious users may be able to gain unauthorized access. 127.0.0.0/8,10.0.0.0/8,172.16.0.0/12,192.168.0.0/16,169.254.0.0/16 127.0.0.0/8,10.0.0.0/8,172.16.0.0/12,192.168.0.0/16,169.254.0.0/16 false
enable_exactly_once (bool) Whether to enable exactly once semantics. true true false
rpc_max_message_size_enable_validation (bool) Whether to turn off validation for --rpc_max_message_size flag. This is a test-only flag. true true false
use_system_auth_to_local (bool) When enabled, use the system krb5 library to map Kerberos principal names to local (short) usernames. If not enabled, the first component of the principal will be used as the short name. For example, 'kudu/foo.example.com@EXAMPLE' will map to 'kudu'. true true false
ipki_server_key_size (int32) the number of bits for server cert's private key. The server cert is used for TLS connections to and from clients and other servers. 2048 2048 false
openssl_security_level_override (int32) if set to 0 or greater, overrides the security level for OpenSSL library of versions 1.1.0 and newer; for test purposes only -1 -1 false
disable_blockbloomfilter_avx2 (bool) Disable AVX2 operations in BlockBloomFilter. This flag has no effect if the target CPU doesn't support AVX2 at run-time or BlockBloomFilter was built with a compiler that doesn't support AVX2. false false false
cache_force_single_shard (bool) Override all cache implementations to use just one shard false false false
cache_memtracker_approximation_ratio (double) The MemTracker associated with a cache can accumulate error up to this ratio to improve performance. For tests. 0.01 0.01 false
trace_to_console (string) Trace pattern specifying which trace events should be dumped directly to the console false
crash_on_eio (bool) Kill the process if an I/O operation results in EIO. If false, I/O resulting in EIOs will return the status IOError and leave error-handling up to the caller. false false false
encrypt_data_at_rest (bool) Whether sensitive files should be encrypted on the file system. false false false
encryption_key_length (int32) Encryption key length. 128 128 false
env_inject_eio (double) Fraction of the time that operations on certain files will fail with the posix code EIO. 0 0 false
env_inject_eio_globs (string) Comma-separated list of glob patterns specifying files on which I/O will fail. By default, all files may cause a failure. * * false
env_inject_lock_failure_globs (string) Comma-separated list of glob patterns specifying files on which attempts to obtain a file lock will fail. By default, no files will fail. false
env_inject_short_read_bytes (int32) The number of bytes less than the requested bytes to read 0 0 false
env_inject_short_write_bytes (int32) The number of bytes less than the requested bytes to write 0 0 false
env_use_fsync (bool) Use fsync(2) instead of fdatasync(2) for synchronizing dirty data to disk. false false false
env_use_ioctl_hole_punch_on_xfs (bool) Use the XFS_IOC_UNRESVSP64 ioctl instead of fallocate(2) to punch holes on XFS filesystems. true true false
never_fsync (bool) Never fsync() anything to disk. This is used by certain test cases to speed up runtime. This is very unsafe to use in production. false false false
disk_reserved_bytes_free_for_testing (int64) For testing only! Set to number of bytes free on each filesystem. Set to -1 to disable this test-specific override -1 -1 false
disk_reserved_override_prefix_1_bytes_free_for_testing (int64) For testing only! Set number of bytes free on the path prefix specified by --disk_reserved_override_prefix_1_path_for_testing. Set to -1 to disable. -1 -1 false
disk_reserved_override_prefix_1_path_for_testing (string) For testing only! Specifies a prefix to override the visible 'bytes free' on. Use --disk_reserved_override_prefix_1_bytes_free_for_testing to set the number of bytes free for this path prefix. Set to empty string to disable. false
disk_reserved_override_prefix_2_bytes_free_for_testing (int64) For testing only! Set number of bytes free on the path prefix specified by --disk_reserved_override_prefix_2_path_for_testing. Set to -1 to disable. -1 -1 false
disk_reserved_override_prefix_2_path_for_testing (string) For testing only! Specifies a prefix to override the visible 'bytes free' on. Use --disk_reserved_override_prefix_2_bytes_free_for_testing to set the number of bytes free for this path prefix. Set to empty string to disable. false
env_inject_full (double) Fraction of the time that space checks on certain paths will yield the posix code ENOSPC. 0 0 false
env_inject_full_globs (string) Comma-separated list of glob patterns specifying which paths return with space errors. * * false
disable_core_dumps (bool) Disable core dumps when this process crashes. false false false
dump_metrics_json (bool) Dump a JSON document describing all of the metrics which may be emitted by this binary. false false false
dump_metrics_xml (bool) Dump an XML document describing all of the metrics which may be emitted by this binary. false false false
redact (string) Comma-separated list that controls redaction context. Supported options are 'all','log', and 'none'. If 'all' is specified, sensitive data (sensitive configuration flags and row data) will be redacted from the web UI as well as glog and error messages. If 'log' is specified, sensitive data will only be redacted from glog and error messages. If 'none' is specified, no redaction will occur. all all false
umask (string) The umask that will be used when creating files and directories. Permissions of top-level data directories will also be modified at start-up to conform to the given umask. Changing this value may enable unauthorized local users to read or modify data stored by Kudu. 077 077 false
unlock_experimental_flags (bool) Unlock flags marked as 'experimental'. These flags are not guaranteed to be maintained across releases of Kudu, and may enable features or behavior known to be unstable. Use at your own risk. false false false
unlock_unsafe_flags (bool) Unlock flags marked as 'unsafe'. These flags are not guaranteed to be maintained across releases of Kudu, and enable features or behavior known to be unsafe. Use at your own risk. false false false
hung_task_check_interval_ms (int32) Number of milliseconds in between checks for hung threads 200 200 false
inject_latency_on_kernel_stack_lookup_ms (int32) Number of milliseconds of latency to inject when reading a thread's kernel stack 0 0 false
log_async (bool) Enable asynchronous writing to log files. This improves latency and stability. true true false
log_async_buffer_bytes_per_level (int32) The number of bytes of buffer space used by each log level. Only relevant when --log_async is enabled. 2097152 2097152 false
allocator_aligned_mode (bool) Use 16-byte alignment instead of 8-byte, unless explicitly specified otherwise - to boost SIMD false false false
metrics_retirement_age_ms (int32) The minimum number of milliseconds a metric will be kept for after it is no longer active. (Advanced option) 120000 120000 false
dns_resolver_cache_capacity_mb (uint32) Capacity of DNS resolver cache, in MiBytes. For each key, the cache stores records returned by getaddrinfo(). A value of 0 means the results of DNS name resolution are not cached. 1 1 false
dns_resolver_cache_ttl_sec (uint32) TTL of records in the DNS resolver cache, in seconds. 15 15 false
dns_resolver_max_threads_num (int32) The maximum number of threads to use for async DNS resolution 1 1 false
dns_addr_resolution_override (string) Comma-separated list of '='-separated pairs of hosts to addresses. The left-hand side of the '=' is taken as a host, and will resolve to the right-hand side which is expected to be a socket address with no port. false
fail_dns_resolution (bool) Whether to fail dns resolution, for tests. false false false
fail_dns_resolution_hostports (string) Comma-separated list of hostports that fail dns resolution. If empty, fails all dns resolution attempts. Only takes effect if --fail_dns_resolution is 'true'. false
host_for_tests (string) Host to use when resolving a given server's locally bound or advertised addresses. false
local_ip_for_outbound_sockets (string) IP to bind to when making outgoing socket connections. This must be an IP address of the form A.B.C.D, not a hostname. Advanced parameter, subject to change. false
socket_inject_short_recvs (bool) Inject short recv() responses which return less data than requested false false false
memory_limit_hard_bytes (int64) Maximum amount of memory this daemon should use, in bytes. A value of 0 autosizes based on the total system memory. A value of -1 disables all memory limiting. 0 0 false
memory_limit_soft_percentage (int32) Percentage of the hard memory limit that this daemon may consume before memory throttling of writes begins. The greater the excess, the higher the chance of throttling. In general, a lower soft limit leads to smoother write latencies but decreased throughput, and vice versa for a higher soft limit. 80 80 false
memory_limit_warn_threshold_percentage (int32) Percentage of the hard memory limit that this daemon may consume before WARNING level messages are periodically logged. 98 98 false
memory_pressure_percentage (int32) Percentage of the hard memory limit that this daemon may consume before flushing of in-memory data becomes prioritized. 60 60 false
thread_inject_start_latency_ms (int32) Number of ms to sleep when starting a new thread. (For tests). 0 0 false
accepted_cnxn_queue_depth (int32) (Advanced) The size of the post-accept, pre-setup connection queue in each thrift server set up to service Impala internal and external connections. 10000 10000 false
accepted_cnxn_setup_thread_pool_size (int32) (Advanced) The size of the thread pool that is used to process the post-accept, pre-setup connection queue in each thrift server set up to service Impala internal and external connections. 2 2 false
cookie_require_secure (bool) (Advanced) If true, authentication cookies will include the 'Secure' attribute, indicating to clients that they should only be returned over SSL connections. For testing only. true true false
max_cookie_lifetime_s (int64) Maximum amount of time in seconds that an authentication cookie will remain valid. Setting to 0 disables use of cookies. Defaults to 1 day. 86400 86400 false
samesite_strict (bool) (Advanced) If true, authentication cookies will include SameSite=Strict. false false false
enable_group_filter_check_for_authenticated_kerberos_user (bool) If this configuration is set to true, Impala checks the provided LDAP group filter, if any, with the authenticated Kerberos user. This should be only enabled if both Kerberos and LDAP authentication are enabled and the users in KDC and LDAP are synchronized (e.g. when the KDC and the LDAP is the same Active Directory server). The default value is false, which provides backwards-compatible behavior. false false false
enable_ldap_auth (bool) If true, use LDAP authentication for client connections false true false
internal_principals_whitelist (string) (Advanced) Comma-separated list of additional usernames authorized to access Impala's internal APIs. Defaults to 'hdfs' which is the system user that in certain deployments must access catalog server APIs. hdfs hdfs false
jwks_ca_certificate (string) File path of a pem bundle of root ca certificates that will be trusted when retrieving the JWKS from the specified JWKS URL. false
jwks_file_path (string) File path of the pre-installed JSON Web Key Set (JWKS) for JWT verification false
jwks_pulling_timeout_s (int32) (Advanced) The time in seconds for connection timed out when pulling JWKS from the specified URL. 10 10 false
jwks_update_frequency_s (int32) (Advanced) The time in seconds to wait between downloading JWKS from the specified URL. 60 60 false
jwks_url (string) URL of the JSON Web Key Set (JWKS) for JWT verification false
jwks_verify_server_certificate (bool) Specifies if the TLS certificate of the JWKS server is verified when retrieving the JWKS from the specified JWKS URL. A certificate is considered valid if a trust chain can be established for it, and if the certificate has a common name or SAN that matches the server's hostname. This should only be set to false for development / testing. true true false
jwt_custom_claim_username (string) Custom claim 'username' username username false
jwt_token_auth (bool) When true, read the JWT token out of the HTTP Header and extract user name from the token payload. false false false
jwt_validate_signature (bool) When true, validate the signature of JWT token with pre-installed JWKS. true true false
ldap_ca_certificate (string) The full path to the certificate file used to authenticate the LDAP server's certificate for SSL / TLS connections. /usr/share/root-certs.pem false
ldap_group_filter (string) Used as filter for both simple and search bind mechanisms. For simple bind it is a comma separated list of groups. If specified, users must belong to one of these groups for authentication to succeed. For search bind it is an LDAP filter that will be used during LDAP group search, it can contain '{0}' pattern which will be replaced with the user name and/or '{1}' which will be replace with the user dn. false
ldap_user_filter (string) Used as filter for both simple and search bind mechanisms. For simple bind it is a comma separated list of user names. If specified, users must be on this list for authentication to succeed. For search bind it is an LDAP filter that will be used during LDAP search, it can contain '{0}' pattern which will be replaced with the user name. (&(objectClass=posixAccount)(cn={0})) false
sasl_path (string) Colon separated list of paths to look for SASL security library plugins. false
trusted_auth_header (string) If set as non empty string, Impala will look for this header in the HTTP headers. If the header is present, Impala will skip authentication and extract the username directly from the authorization header. Currently, only connections over HTTP support this. Note: It still requires the client to specify a username via the Basic Authorization header in the format <username>:<password> where the password is not used and can be left blank. Warning: Only use this flag if the connections are authenticated before the requests land on Impala so that Impala can avoid the authentication again. The system must remove the trusted HTTP headers from any requests that come from outside the system. false
trusted_domain (string) If set, Impala will skip authentication for connections originating from this domain. Currently, only connections over HTTP support this. Note: It still requires the client to specify a username via the Basic Authorization header in the format <username>:<password> where the password is not used and can be left blank. false
trusted_domain_empty_xff_header_use_origin (bool) If set to true and the 'X-Forwarded-For' HTML header value is empty in the request, then the origin of the the underlying transport is used while attempting to verify if the connection request originated from a trusted domain. Only used if '--trusted_domain' and '--trusted_domain_use_xff_header' flags are specified. Warning: In case the 'X-Forwarded-For' HTML header is empty or not in the request, this flag allows a fallback to the default behavior in trusted domain check (where '--trusted_domain' flag is specified, but '--trusted_domain_use_xff_header' flag is not set). false false false
trusted_domain_strict_localhost (bool) If set to true and trusted_domain='localhost', this will not use reverse DNS to determine if something is from localhost. It will only match 127.0.0.1. This is important for security, because reverse DNS can resolve other non-local addresses to localhost. true true false
trusted_domain_use_xff_header (bool) If set to true, this uses the 'X-Forwarded-For' HTML header to check for origin while attempting to verify if the connection request originated from a trusted domain. Only used if '--trusted_domain' is specified. Warning: Only use this if you trust the incoming connection to have this set correctly. false false false
num_acceptor_threads (int32) Number of threads dedicated to accepting connection requests for RPC services 2 2 false
num_reactor_threads (int32) Number of threads dedicated to managing network IO for RPC services. If left at default value 0, it will be set to number of CPU cores. 0 0 false
rpc_negotiation_thread_count (int32) Maximum number of threads dedicated to handling RPC connection negotiations. 64 64 false
rpc_negotiation_timeout_ms (int32) Time in milliseconds of waiting for a negotiation to complete before timing out. 300000 300000 false
rpc_retry_interval_ms (int32) Time in millisecond of waiting before retrying an RPC when remote is busy 5 5 false
rpc_use_loopback (bool) Always use loopback for local connections. This requires binding to all addresses, not just the KRPC address. false false false
rpc_use_unix_domain_socket (bool) Whether the KRPC client and server should use Unix domain socket. If enabled, each daemon is identified with Unix Domain Socket address in the unique name in "Abstract Namespace", in format @impala-krpc:<BackendId>. The KRPC server bind to a Unix domain socket. KRPC Client attempt to connect to KRPC server via a Unix domain socket. false false false
uds_address_unique_id (string) Specify unique Id for UDS address. It could be "ip_address", "backend_id", or "none" ip_address ip_address false
thrift_external_rpc_max_message_size (int64) The maximum size of a message for external client RPC communication. This defaults to 2GB to limit the impact of untrusted payloads. This must be set to at least the default defined in Thrift (100MB). Setting 0 or a negative value will use the default defined in Thrift. 2147483648 2147483648 false
thrift_rpc_max_message_size (int64) The maximum size of a message for intra-cluster RPC communication between Impala components. Default to a high limit of 64GB. This must be set to at least the default defined in Thrift (100MB). Setting 0 or a negative value will use the default defined in Thrift. 68719476736 68719476736 false
aws_config_dir (string) Directory that stores config and credentials files for AWS SDK S3 ~/.aws /opt/impala/conf/.aws false
concurrent_scratch_ios_per_device (int32) Set this to influence the number of concurrent write I/Os issues to write data to scratch files. This is multiplied by the number of active scratch directories to obtain the target number of scratch write I/Os per query. 2 2 false
madvise_huge_pages (bool) (Advanced) If true, advise operating system to back large memory buffers with huge pages true true false
mmap_buffers (bool) (Experimental) If true, allocate buffers directly from the operating system instead of with TCMalloc. false false false
insert_inherit_permissions (bool) If true, new directories created by INSERTs will inherit the permissions of their parent directories false false false
admission_control_slots (int32) (Advanced) The maximum degree of parallelism to run queries with on this backend. This determines the number of slots available to queries in admission control for this backend. The degree of parallelism of the query determines the number of slots that it needs. Defaults to number of cores / -num_cores for executors, and 8x that value for dedicated coordinators). 0 32 false
backend_client_connection_num_retries (int32) Retry backend connections. 3 3 false
backend_client_rpc_timeout_ms (int32) (Advanced) The underlying TSocket send/recv timeout in milliseconds for a backend client RPC. 300000 300000 false
catalog_client_connection_num_retries (int32) The number of times connections or RPCs to the catalog should be retried. 10 10 false
catalog_client_rpc_retry_interval_ms (int32) (Advanced) The time to wait before retrying when the catalog RPC client fails to connect to catalogd or when RPCs to the catalogd fail. 3000 3000 false
catalog_client_rpc_timeout_ms (int32) (Advanced) The underlying TSocket send/recv timeout in milliseconds for a catalog client RPC. The default is 10 hours. Operations take longer than this are usually abnormal and hanging. 36000000 36000000 false
catalog_lightweight_rpc_timeout_ms (int32) (Advanced) The underlying TSocket send/recv timeout in milliseconds for a lightweight catalog RPC which shouldn't take long in catalogd, e.g. fetching db/table list. The default is 30 minutes which is long enough to tolerate TCP timeout due to retransmission. 1800000 1800000 false
catalog_service_host (string) hostname where CatalogService is running localhost localhost false
codegen_cache_capacity (string) Specify the capacity of the codegen cache. If set to 0, codegen cache is disabled. 1GB 1GB false
enable_webserver (bool) If true, debug webserver is enabled true true false
local_catalog_cache_concurrency_level (int32) If --use_local_catalog is enabled, configures the local cache's concurrency level to avoid lock contention, the default value 4 is consistent with the default value of the original cache. 4 4 false
local_catalog_cache_expiration_s (int32) If --use_local_catalog is enabled, configures the expiration time of the catalog cache within each impalad. Even if the configured cache capacity has not been reached, items are removed from the cache if they have not been accessed in this amount of time. 3600 3600 false
local_catalog_cache_mb (int32) If --use_local_catalog is enabled, configures the size of the catalog cache within each impalad. If this is set to -1, the cache is auto-configured to 60% of the configured Java heap size. Note that the Java heap size is distinct from and typically smaller than the overall Impala memory limit. -1 -1 false
local_catalog_max_fetch_retries (int32) If --use_local_catalog is enabled, configures the maximum number of times the frontend retries when fetching a metadata object from the impalad coordinator's local catalog cache. 40 40 false
max_concurrent_queries (int32) (Deprecated) This has been replaced with --admission_control_slots, which better accounts for the higher parallelism of queries with mt_dop > 1. If --admission_control_slots is not set, the value of --max_concurrent_queries is used instead for backward compatibility. 0 0 false
metrics_webserver_interface (string) Interface to start metrics webserver on. If blank, webserver binds to 0.0.0.0 false
metrics_webserver_port (int32) If non-zero, the port to run the metrics webserver on, which exposes the /metrics, /jsonmetrics, /metrics_prometheus, and /healthz endpoints without authentication enabled. 0 25090 false
num_hdfs_worker_threads (int32) (Advanced) The number of threads in the global HDFS operation pool 16 16 false
ping_expose_webserver_url (bool) If true, debug webserver url is exposed via PingImpalaService/PingImpalaHS2Service RPC calls true true false
state_store_subscriber_port (int32) port where StatestoreSubscriberService should be exported 23000 23000 false
use_local_catalog (bool) Use the on-demand metadata feature in coordinators. If this is set, coordinators pull metadata as needed from catalogd and cache it locally. The cached metadata gets evicted automatically under memory pressure or after an expiration time. false true false
s3a_access_key_cmd (string) A Unix command whose output returns the access key to S3, i.e. "fs.s3a.access.key". false
s3a_secret_key_cmd (string) A Unix command whose output returns the secret key to S3, i.e. "fs.s3a.secret.key". false
data_cache_anonymize_trace (bool) (Advanced) Use hashes of filenames rather than file paths in the data cache access trace. false false false
data_cache_async_write_buffer_limit (string) (Experimental) Limit of the total buffer size used by asynchronous store tasks. 1GB 1GB false
data_cache_checksum (bool) (Advanced) Enable checksumming for the cached buffer. false false false
data_cache_enable_tracing (bool) (Advanced) Collect a trace of all lookups in the data cache. false false false
data_cache_eviction_policy (string) (Advanced) The cache eviction policy to use for the data cache. Either 'LRU' (default) or 'LIRS' (experimental) LRU LRU false
data_cache_file_max_size_bytes (int64) (Advanced) The maximum size which a cache file can grow to before data stops being appended to it. 1099511627776 1099511627776 false
data_cache_max_opened_files (int32) (Advanced) The maximum number of allowed opened files. This must be at least the number of specified partitions. 1000 1000 false
data_cache_trace_dir (string) The base directory for data cache tracing. The data cache trace files for each cache directory are placed in separate subdirectories underneath this base directory. If blank, defaults to <log_file_dir>/data_cache_trace/ false
data_cache_trace_percentage (int32) The percentage of cache lookups that should be emitted to the trace file. 100 100 false
data_cache_write_concurrency (int32) (Advanced) Number of concurrent threads allowed to insert into the cache per partition; unset uses 1 for rotational disks and 8 for solid state disks. 0 0 false
max_data_cache_trace_file_size (int32) The maximum size (in log entries) of the data cache trace file before a new one is created. 100000 100000 false
max_data_cache_trace_files (int32) Maximum number of data cache trace files to retain for each cache directory specified by the data_cache startup parameter. The most recent trace files are retained. If set to 0, all trace files are retained. 10 10 false
cache_abfs_file_handles (bool) Enable the file handle cache for ABFS files. true true false
cache_ozone_file_handles (bool) Enable the file handle cache for Ozone files. true true false
cache_remote_file_handles (bool) Enable the file handle cache for remote HDFS files. true true false
cache_s3_file_handles (bool) Enable the file handle cache for S3 files. true true false
data_cache (string) The configuration string for IO data cache. Default to be an empty string so it's disabled. The configuration string is expected to be a list of directories, separated by ',', followed by a ':' and a capacity quota per directory. For example /data/0,/data/1:1TB means the cache may use up to 2TB, with 1TB max in /data/0 and /data/1 respectively. Please note that each Impala daemon on a host must have a unique caching directory. false
data_cache_keep_across_restarts (bool) (Experimental) If this is true, the data cache metadata is dumped to the same directory as the cached files on disk when the process gracefully shutdowns. The metadata will be reloaded the next time the process starts, so that the previous cached data can be reused as if the process had never shutdown. If loading fails, it will proceed with regular initialization. false false false
data_cache_num_async_write_threads (int32) (Experimental) Number of data cache async write threads. Write threads will write the cache asynchronously after IO thread read data, so IO thread will return more quickly. The extra memory for temporary buffers is limited by --data_cache_async_write_buffer_limit. If this's 0, then write will be synchronous. 0 0 false
max_cached_file_handles (uint64) Maximum number of HDFS file handles that will be cached. Disabled if set to 0. 20000 20000 false
num_abfs_io_threads (int32) Number of ABFS I/O threads 16 16 false
num_adls_io_threads (int32) Number of ADLS I/O threads 16 16 false
num_cos_io_threads (int32) Number of COS I/O threads 16 16 false
num_disks (int32) Number of disks on data node. 0 0 false
num_file_handle_cache_partitions (uint64) Number of partitions used by the file handle cache. 16 16 false
num_gcs_io_threads (int32) Number of GCS I/O threads 16 16 false
num_io_threads_per_rotational_disk (int32) Number of I/O threads per rotational disk. Has priority over num_threads_per_disk. If neither is set, defaults to 1 thread(s) per rotational disk 0 4 false
num_io_threads_per_solid_state_disk (int32) Number of I/O threads per solid state disk. Has priority over num_threads_per_disk. If neither is set, defaults to 8 thread(s) per solid state disk 0 0 false
num_obs_io_threads (int32) Number of OBS I/O threads 16 16 false
num_oss_io_threads (int32) Number of OSS/JindoFS I/O threads 16 16 false
num_ozone_io_threads (int32) Number of Ozone I/O threads 16 16 false
num_remote_hdfs_file_oper_io_threads (int32) Number of remote HDFS file operations I/O threads 8 8 false
num_remote_hdfs_io_threads (int32) Number of remote HDFS I/O threads 8 8 false
num_s3_file_oper_io_threads (int32) Number of S3 file operations I/O threads 16 32 false
num_s3_io_threads (int32) Number of S3 I/O threads 16 32 false
num_sfs_io_threads (int32) Number of SFS I/O threads 16 16 false
num_threads_per_disk (int32) Number of I/O threads per disk 0 10 false
unused_file_handle_timeout_sec (uint64) Maximum time, in seconds, that an unused HDFS file handle will remain in the file handle cache. Disabled if set to 0. 21600 21600 false
fs_slow_read_log_threshold_ms (int64) Log diagnostics about I/Os issued via the HDFS client that take longer than this threshold. 10000 10000 false
fs_trace_remote_reads (bool) (Advanced) Log block locations for remote reads. false false false
use_hdfs_pread (bool) Enables using hdfsPread() instead of hdfsRead() when performing HDFS read operations. This is necessary to use HDFS hedged reads (assuming the HDFS client is configured to do so). Preads are always enabled for S3A and ABFS reads. false false false
hdfs_operation_timeout_sec (uint64) Maximum time, in seconds, that an HDFS operation should wait before timing out and failing. 300 300 false
datastream_sender_timeout_ms (int32) (Advanced) The time, in ms, that can elapse before a plan fragment will time-out trying to send the initial row batch. 120000 120000 false
datastream_service_deserialization_queue_size (int32) Number of deferred RPC requests that can be enqueued before being processed by a deserialization thread. 10000 10000 false
datastream_service_num_deserialization_threads (int32) Number of threads for deserializing RPC requests deferred due to the receiver not ready or the soft limit of the receiver is reached. 16 16 false
data_stream_sender_buffer_size (int64) (Advanced) Max size in bytes which a row batch in a data stream sender's channel can accumulate before the row batch is sent over the wire. 16384 16384 false
dump_exec_request_path (string) If set, dump TExecRequest structures to {dump_exec_request_path}/TExecRequest-{internal|external}.{query_id.hi}-{query_id.lo} false
log_mem_usage_interval (int32) If non-zero, impalad will output memory usage every log_mem_usage_interval'th fragment completion. 0 0 false
query_exec_mgr_cancellation_thread_pool_size (int32) (Advanced) Size of the QueryExecMgr thread-pool processing cancellations due to coordinator failure 1 1 false
max_filter_error_rate (double) (Advanced) The target false positive probability used to determine the ideal size for each bloom filter size. This value can be overriden by the RUNTIME_FILTER_ERROR_RATE query option. 0.10000000000000001 0.10000000000000001 false
max_error_logs_per_instance (int32) Maximum number of non-fatal error to be logged in log level 1 (INFO). Once this number exceeded, further non-fatal error will be logged at log level 2 (DEBUG) severity. This flag is ignored if user set negative max_errors query option. Default to 2000 2000 2000 false
num_threads_per_core (int32) Number of threads per core. 3 3 false
allow_multiple_scratch_dirs_per_device (bool) If false and --scratch_dirs contains multiple directories on the same device, then only the first writable directory is used true true false
disk_spill_compression_buffer_limit_bytes (int64) (Advanced) Limit on the total bytes of compression buffers that will be used for spill-to-disk compression across all queries. If this limit is exceeded, some data may be spilled to disk in uncompressed form. 536870912 536870912 false
disk_spill_compression_codec (string) (Advanced) If set, data will be compressed using the specified compression codec before spilling to disk. This can substantially reduce scratch disk usage, at the cost of requiring more CPU and memory resources to compress the data. Uses the same syntax as the COMPRESSION_CODEC query option, e.g. 'lz4', 'zstd', 'zstd:6'. If this is set, then --disk_spill_punch_holes must be enabled. false
disk_spill_encryption (bool) Set this to encrypt and perform an integrity check on all data spilled to disk during a query true false false
disk_spill_punch_holes (bool) (Advanced) changes the free space management strategy for files created in --scratch_dirs to punch holes in the file when space is unused. This can reduce the amount of scratch space used by queries, particularly in conjunction with disk spill compression. This option requires the filesystems of the directories in --scratch_dirs to support hole punching. false false false
remote_batch_read (bool) Set if the system uses batch reading for the remote temporary files. Batch readingallows reading a block asynchronously when the buffer pool is trying to pin onepage of that block. false false false
remote_read_memory_buffer_size (string) Specify the maximum size of read memory buffers for the remote temporary files. Only valid when --remote_batch_read is true. 1G 1G false
remote_tmp_file_block_size (string) Specify the size of the block for doing file uploading and fetching. The block size should be power of 2 and less than the size of remote temporary file. 1M 1M false
remote_tmp_file_size (string) Specify the size of a remote temporary file. Upper bound is 256MB. Lower bound is the block size. The size should be power of 2 and integer times of the block size. 16M 16M false
remote_tmp_files_avail_pool_lifo (bool) If true, lifo is the algo to evict the local buffer files during spilling to the remote. Otherwise, fifo would be used. false false false
scratch_dirs (string) Writable scratch directories. This is a comma-separated list of directories. Each directory is specified as the directory path, an optional limit on the bytes that will be allocated in that directory, and an optional priority for the directory. If the optional limit is provided, the path and the limit are separated by a colon. E.g. '/dir1:10G,/dir2:5GB,/dir3' will allow allocating up to 10GB of scratch in /dir1, 5GB of scratch in /dir2 and an unlimited amount in /dir3. If the optional priority is provided, the path and the limit and priority are separated by colon. Priority based spilling will result in directories getting selected as a spill target based on their priority. The lower the numerical value the higher the priority. E.g. '/dir1:10G:0,/dir2:5GB:1,/dir3::1', will cause spilling to first fill up '/dir1' followed by using '/dir2' and '/dir3' in a round robin manner. /tmp /tmp false
wait_for_spill_buffer_timeout_s (int32) Specify the timeout duration waiting for the buffer to write (second). If a spillingopertion fails to get a buffer from the pool within the duration, the operationfails. 60 60 false
allow_tuple_caching (bool) If false, tuple caching cannot be used. false false false
tuple_cache (string) The configuration string for the tuple cache. The default is the empty string, which disables the tuple cache. The configuration string is expected to be a directory followed by a ':' and a capacity quota. For example, /data/0:1TB means the cache may use 1TB in /data/0. Please note that each Impala daemon on a host must have a unique cache directory. false
tuple_cache_eviction_policy (string) (Advanced) The cache eviction policy to use for the tuple cache. Either 'LRU' (default) or 'LIRS' (experimental) LRU LRU false
admission_control_service_num_svc_threads (int32) Number of threads for processing admission control service's RPCs. if left at default value 0, it will be set to number of CPU cores. Set it to a positive value to change from the default. 0 0 false
admission_control_service_queue_mem_limit (string) (Advanced) Limit on RPC payloads consumption for AdmissionControlService. Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of the process memory limit ('<int>%'). Defaults to bytes if no unit is given. 50MB 50MB false
admission_service_host (string) If provided, queries submitted to this impalad will be scheduled and admitted by contacting the admission control service at the specified address and --admission_service_port. false
admission_status_wait_time_ms (int32) (Advanced) The number of milliseconds the GetQueryStatus() rpc in the admission control service will wait for admission to complete before returning. 100 100 false
admission_thread_pool_size (int32) (Advanced) Size of the thread-pool processing AdmitQuery requests. 5 5 false
max_admission_queue_size (int32) (Advanced) Max size of the queue for the AdmitQuery thread pool. 50 50 false
admiss_use_mem_estimate (bool) If false AND resource pool has not set max or min mem limit AND no mem_limit is set for query - when query is admitted to pool mem limit estimate is used to check if query can be started - pool available memory > mem estimate * num backend nodes - but during execution query has no limit on memory consumption.If true query memory is always limited during execution with estimated mem limit if no explicit mem limit is set. false false false
balance_queries_across_executor_groups (bool) If true, balance queries across multiple groups that belonging to the same request pool based on available memory and slots in each executor group. If false, admission is attempted to groups in alphanumerically sorted order. false false false
clamp_query_mem_limit_backend_mem_limit (bool) Caps query memory limit to memory limit for admission on the backends. The coordinator memory limit is capped to the coordinator backend's memory limit, while executor memory limit is capped to the effective or minimum memory limit for admission on executor backends. If the flag is not set, a query requesting more than backend's memory limit for admission gets rejected during admission. However, if this flag is set, such a query gets admitted with backend's memory limit and could succeed if the memory request was over estimated and could fail if query really needs more memory. true true false
queue_wait_timeout_ms (int64) Maximum amount of time (in milliseconds) that a request will wait to be admitted before timing out. 60000 60000 false
wait_mem_limit (double) Maximum memory limit for wait queue 0.75 0.75 false
admission_service_port (int32) The port where the admission control service runs 29500 29500 false
blacklisting_enabled (bool) (Advanced) If false, disables local blacklisting of executors by coordinators, which temporarily removes executors that appear to be problematic from scheduling decisions. true true false
admission_max_retry_time_s (int32) (Advanced) The amount of time in seconds the coordinator will spend attempting to retry admission if the admissiond is unreachable. 60 60 false
admission_status_retry_time_ms (int32) (Advanced) The number of milliseconds coordinators will wait before retrying the GetQueryStatus rpc. 10 10 false
default_pool_max_queued (int64) Maximum number of requests allowed to be queued before rejecting requests. A negative value or 0 indicates requests will always be rejected once the maximum number of concurrent requests are executing. Ignored if fair_scheduler_config_path and llama_site_path are set. 200 200 false
default_pool_max_requests (int64) Maximum number of concurrent outstanding requests allowed to run before queueing incoming requests. A negative value indicates no limit. 0 indicates no requests will be admitted. Ignored if fair_scheduler_config_path and llama_site_path are set. -1 -1 false
default_pool_mem_limit (string) Maximum amount of memory that all outstanding requests in this pool may use before new requests to this pool are queued. Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of the physical memory ('<int>%'). Defaults to bytes if no unit is given. Ignored if fair_scheduler_config_path and llama_site_path are set. false
disable_pool_max_requests (bool) Disables all per-pool limits on the maximum number of running requests. false false false
disable_pool_mem_limits (bool) Disables all per-pool mem limits. false false false
fair_scheduler_allocation_path (string) Path to the fair scheduler allocation file (fair-scheduler.xml). /opt/impala/conf/admission/fair-scheduler.xml false
llama_site_path (string) Path to the Llama configuration file (llama-site.xml). If set, fair_scheduler_allocation_path must also be set. /opt/impala/conf/admission/llama-site.xml false
require_username (bool) Requires that a user be provided in order to schedule requests. If enabled and a user is not provided, requests will be rejected, otherwise requests without a username will be submitted with the username 'default'. false false false
control_service_num_svc_threads (int32) Number of threads for processing control service's RPCs. if left at default value 0, it will be set to number of CPU cores. Set it to a positive value to change from the default. 0 0 false
control_service_queue_mem_limit (string) (Advanced) Limit on RPC payloads consumption for ControlService. Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of the process memory limit ('<int>%'). Defaults to bytes if no unit is given. 1% 1% false
control_service_queue_mem_limit_floor_bytes (int64) Lower bound on --control_service_queue_mem_limit in bytes. If --control_service_queue_mem_limit works out to be less than this amount, this value is used instead 52428800 52428800 false
datastream_service_num_svc_threads (int32) Number of threads for processing datastream services' RPCs. If left at default value 0, it will be set to number of CPU cores. Set it to a positive value to change from the default. 0 0 false
datastream_service_queue_mem_limit (string) (Advanced) Limit on RPC payloads consumption for DataStreamService. Specified as number of bytes ('<int>[bB]?'), megabytes ('<float>[mM]'), gigabytes ('<float>[gG]'), or percentage of the process memory limit ('<int>%'). Defaults to bytes if no unit is given. 5% 5% false
allow_catalog_cache_op_from_masked_users (bool) Whether to allow table level catalog-cache operations, i.e. REFRESH/INVALIDATE METADATA <table>, from users that have associate Ranger masking policies on the table. By default, such operations are blocked since such users are considered read-only users. Note that checking column masking policies requires loading column info of the table, which could slow down simple commands like INVALIDATE METADATA <table> false false false
authorization_factory_class (string) Specifies the class name that implements the authorization provider. This will override the authorization_provider flag if both are specified. false
authorization_provider (string) Specifies the type of internally-provided authorization provider to use. Defaults to unset, which disables authorization. To enable authorization, set to one of the following: ['ranger'] false
authorized_proxy_group_config (string) Specifies the set of authorized proxy groups (users who can delegate to other users belonging to the specified groups during authorization) and whom they are allowed to delegate. Input is a semicolon-separated list of key=value pairs of authorized proxy users to the group(s) they can delegate to. These groups are specified as a list of groups separated by a delimiter (which defaults to comma and may be changed via --authorized_proxy_group_config_delimiter), or '*' to indicate all users. For example: hue=group1,group2;admin=* false
authorized_proxy_group_config_delimiter (string) Specifies the delimiter used in authorized_proxy_group_config. , , false
authorized_proxy_user_config (string) Specifies the set of authorized proxy users (users who can delegate to other users during authorization) and whom they are allowed to delegate. Input is a semicolon-separated list of key=value pairs of authorized proxy users to the user(s) they can delegate to. These users are specified as a list of short usernames separated by a delimiter (which defaults to comma and may be changed via --authorized_proxy_user_config_delimiter), or '*' to indicate all users. For example: hue=user1,user2;admin=* psantos=* false
authorized_proxy_user_config_delimiter (string) Specifies the delimiter used in authorized_proxy_user_config. , , false
catalog_hms_hook_class_name (string) Class that implements HiveMetaHook for Impala HMS client false
db_list_invalidate_on_event (string) When Catalogd process ALTER Hive Metastore events if database of table is in db_list_invalidate_on_event,normal processing is skipped, table is invalidated (like after executing INVALIDATE METADATA) false
dbcp_data_source_idle_timeout_s (int32) Timeout value in seconds for idle DBCP DataSource objects in cache. It only takes effect when query option 'clean_dbcp_ds_cache' is set as false. 300 300 false
dbcp_max_conn_pool_size (int32) The maximum number of active connections that can be allocated from a DBCP connection pool at the same time, or -1 for no limit. DBCP connection pools are created when accessing remote RDBMS for external JDBC tables. This setting applies to all DBCP connection pools created on the coordinator. 8 8 false
dbcp_max_wait_millis_for_conn (int32) The maximum number of milliseconds that DBCP connection pool will wait (when there are no available connections) for a connection to be returned before throwing an exception, or -1 to wait indefinitely. 0 means immediately throwing exception if there are no available connections in the pool. -1 -1 false
enable_kudu_impala_hms_check (bool) By default this flag is true. If enabled checks that Kudu and Impala are using the same HMS instance(s). true true false
enable_shell_based_groups_mapping_support (bool) Enables support for Hadoop groups mapping org.apache.hadoop.security.ShellBasedUnixGroupsMapping. By default this support is not enabled as it can lead to many process getting spawned to fetch groups for user using shell command. false false false
iceberg_cache_concurrency_level (int32) If --iceberg_use_last_table_version is enabled, configures the local cache's concurrency level to avoid lock contention, the default value 4 is consistent with the default value of the original cache. 4 4 false
iceberg_cache_expiration_s (int32) If --iceberg_use_last_table_version is enabled, configures the expiration time of the cache within each impalad. Even if the configured cache capacity has not been reached, items are removed from the cache if they have not been accessed in this amount of time. 300 300 false
iceberg_cache_in_catalog (bool) If false impalad and catalogd doesn't cache iceberg metadata files + impalad always read from current version of Iceberg table.Enable Iceberg metadata caching (iceberg.io.manifest.cache-enabled=true, etc) when iceberg_cache_in_catalog=false, otherwise retreiving iceberg metadata may case performance degradation. true true false
iceberg_cache_max_size_mb (int32) If --iceberg_use_last_table_version is enabled, configures max size of the cache 100 100 false
iceberg_use_last_table_version (bool) Allows using the current version of Iceberg tables even if the latest version has not yet been loaded into the catalog. false false false
jdbc_tables_credentials_path (string) Specifies the path for jdbc tables credentials files /opt/impala/conf/jdbc-credentials/ /opt/impala/conf/jdbc-credentials/ false
jni_frontend_class (string) By default the JniFrontend class included in the repository is used as the frontend interface. This option allows the class to be overridden by a third party module. The overridden class needs to contain all the methods in the methods[] variable, so most implementations should make their class a child of JniFrontend and override only relevant methods. org/apache/impala/service/JniFrontend org/apache/impala/service/JniFrontend false
kudu_master_hosts (string) Specifies the default Kudu master(s). The given value should be a comma separated list of hostnames or IP addresses; ports are optional. false
ranger_app_id (string) Specifies the Ranger application ID. Ranger application ID is an ID to uniquely identify the application that communicates with Ranger. This flag is required when authorization with Ranger is enabled. false
ranger_service_type (string) Specifies the Ranger service type. hive hive false
server_name (string) The name to use for securing this impalad server during authorization. Set to enable authorization. false
abort_on_failed_audit_event (bool) Shutdown Impala if there is a problem recording an audit event. true false false
abort_on_failed_lineage_event (bool) Shutdown Impala if there is a problem recording a lineage record. true false false
accepted_client_cnxn_timeout (int64) (Advanced) The amount of time in milliseconds an accepted connection will wait in the post-accept, pre-setup connection queue before it is timed out and the connection request is rejected. A value of 0 means there is no timeout. 300000 600000 false
admission_heartbeat_frequency_ms (int32) (Advanced) The time in milliseconds to wait between sending heartbeats to the admission service, if enabled. Heartbeats are used to ensure resources are properly accounted for even if rpcs to the admission service occasionally fail. 1000 1000 false
arrow_flight_port (int32) arrow flight server port to listen on 32010 32010 false
arrow_flight_server_start (bool) arrow flight impala server start false true false
audit_event_log_dir (string) The directory in which audit event log files are written. Setting this flag will enable audit event logging. /opt/impala/logs/impala/audit false
auto_check_compaction (bool) When true, compaction checking will be conducted for each query in local catalog mode. Note that this checking introduces additional overhead because Impala makes additional RPCs to hive metastore for each table in a query during the query compilation. false false false
beeswax_port (int32) port on which Beeswax client requests are served.If 0 or less, the Beeswax server is not started. This interface is deprecated and will be removed in a future version. 21000 21000 false
cancellation_thread_pool_size (int32) (Advanced) Size of the thread-pool processing cancellations due to node failure 5 5 false
convert_legacy_hive_parquet_utc_timestamps (bool) When true, TIMESTAMPs read from files written by Parquet-MR (used by Hive) will be converted from UTC to local time. Writes are unaffected. Can be overriden with the query option with the same name. false false false
default_query_options (string) key=value pair of default query options for impalad, separated by ',' default_file_format=parquet,DEFAULT_HINTS_INSERT_STATEMENT=NOCLUSTERED,DEFAULT_JOIN_DISTRIBUTION_MODE=SHUFFLE,FETCH_ROWS_TIMEOUT_MS=0,COMPRESSION_CODEC=ZSTD,ENABLE_OUTER_JOIN_TO_INNER_TRANSFORMATION=1,UTF8_MODE=TRUE false
disconnected_session_timeout (int32) The time, in seconds, that a hiveserver2 session will be maintained after the last connection that it has been used over is disconnected. 900 600 false
disconnected_session_timeout_http (int32) The time, in seconds, that a hiveserver2 http session will be maintained after the last connection that it has been used over is disconnected. 0 1800 false
enable_external_fe_http (bool) if true enables http transport for external_fe_port otherwise binary transport is used false false false
executor_groups (string) List of executor groups, separated by comma. Each executor group specification can optionally contain a minimum size, separated by a ':', e.g. --executor_groups default-pool-1:3. Default minimum size is 1. Only when the cluster membership contains at least that number of executors for the group will it be considered healthy for admission. Currently only a single group may be specified. false
expected_executor_group_sets (string) Only used by the coordinator. List of expected executor group sets, separated by comma in the following format: <executor_group_name_prefix>:<expected_group_size> . For eg. “prefix1:10”, this set will include executor groups named like prefix1-group1, prefix1-group2, etc. The expected group size (number of executors in each group) is used during planning when no healthy executor group is available. If this flag is used then any executor groups that do not map to the specified group sets will never be used to schedule queries. false
external_fe_port (int32) port on which External Frontend requests are served. If 0 or less, the External Frontend server is not started. Careful consideration must be taken when enabling due to the fact that this port is currently always unauthenticated. 0 21150 false
fe_service_threads (int32) number of threads available to serve client requests 64 512 false
hs2_http_port (int32) port on which HiveServer2 HTTP(s) client requests are served. If 0 or less, the HiveServer2 http server is not started. 28000 28000 false
hs2_port (int32) port on which HiveServer2 client requests are served.If 0 or less, the HiveServer2 server is not started. 21050 21050 false
idle_client_poll_period_s (int32) The poll period, in seconds, after no activity from an Impala client which an Impala service thread (beeswax and HS2) wakes up to check if the connection should be closed. If --idle_session_timeout is also set, a client connection will be closed if all the sessions associated with it have become idle. Set this to 0 to disable the polling behavior and clients' connection will remain opened until they are explicitly closed. 30 30 false
idle_query_timeout (int32) The time, in seconds, that a query may be idle for (i.e. no processing work is done and no updates are received from the client) before it is cancelled. If 0, idle queries are never expired. The query option QUERY_TIMEOUT_S overrides this setting, but, if set, --idle_query_timeout represents the maximum allowable timeout. 0 900 false
idle_session_timeout (int32) The time, in seconds, that a session may be idle for before it is closed (and all running queries cancelled) by Impala. If 0, idle sessions are never expired. It can be overridden by the query option 'idle_session_timeout' for specific sessions 0 1800 false
immutable_query_options (string) Comma-separated list of query option names that users are not allowed to override false
is_coordinator (bool) If true, this Impala daemon can accept and coordinate queries from clients. If false, it will refuse client connections. true true false
is_executor (bool) If true, this Impala daemon will execute query fragments. true true false
lineage_event_log_dir (string) The directory in which lineage event log files are written. Setting this flag with enable lineage logging. /opt/impala/logs/impala/lineage false
log_query_to_file (bool) if true, logs completed query profiles to file. true true false
max_audit_event_log_file_size (int32) The maximum size (in queries) of the audit event log file before a new one is created (if event logging is enabled) 5000 5000 false
max_audit_event_log_file_size_mb (int32) The maximum size (in Mb) of the audit event log file before a new one is created (if event logging is enabled) 100 100 false
max_audit_event_log_files (int32) Maximum number of audit event log files to retain. The most recent audit event log files are retained. If set to 0, all audit event log files are retained. 0 0 false
max_hs2_sessions_per_user (int32) The maximum allowed number of HiveServer2 sessions that can be opened by any single connected user on a coordinator. If set to -1 or 0 then this check is not performed. If set to a positive value then the per-user session count is viewable in the webui under /sessions. -1 -1 false
max_lineage_log_file_size (int32) The maximum size (in queries) of the lineage event log file before a new one is created (if lineage logging is enabled) 5000 5000 false
max_lineage_log_file_size_mb (int32) The maximum size (in Mb) of the lineage event log file before a new one is created (if lineage logging is enabled) 100 100 false
max_lineage_log_files (int32) Maximum number of lineage log files to retain. The most recent log files are retained. If set to 0, all log files are retained. 10 10 false
max_profile_log_file_size (int32) The maximum size (in queries) of the profile log file before a new one is created 5000 5000 false
max_profile_log_file_size_mb (int32) The maximum size (in Mb) of the profile log file before a new one is created 100 100 false
max_profile_log_files (int32) Maximum number of profile log files to retain. The most recent log files are retained. If set to 0, all log files are retained. 10 10 false
max_result_cache_size (int64) Maximum number of query results a client may request to be cached on a per-query basis to support restarting fetches. This option guards against unreasonably large result caches requested by clients. Requests exceeding this maximum will be rejected. 100000 100000 false
num_expected_executors (int32) The number of executors that are expected to be available for the execution of a single query. This value is used during planning if no executors have started yet. Once a healthy executor group has started, its size is used instead. NOTE: This flag is overridden by 'expected_executor_group_sets' which is a more expressive way of specifying multiple executor group sets 20 20 false
profile_log_dir (string) The directory in which profile log files are written. If blank, defaults to <log_file_dir>/profiles /opt/impala/logs/profiles/ false
query_event_hook_classes (string) Comma-separated list of java QueryEventHook implementation classes to load and register at Impala startup. Class names should be fully-qualified and on the classpath. Whitespace acceptable around delimiters. false
query_event_hook_nthreads (int32) Number of threads to use for QueryEventHook execution. If this number is >1 then hooks will execute concurrently. 1 1 false
query_log_size (int32) Number of queries to retain in the query log. If -1, the query log has unbounded size. Used in combination with query_log_size_in_bytes, whichever is less. 200 200 false
query_log_size_in_bytes (int64) Total maximum bytes of queries to retain in the query log. If -1, the query log has unbounded size. Used in combination with query_log_size, whichever is less 2147483648 2147483648 false
query_stmt_size (int32) length of the statements in the query log. If <=0, the full statement is displayed in the query log without trimming. 250 250 false
shutdown_deadline_s (int64) Default time limit in seconds for the shut down process. If this duration elapses after the shut down process is started, the daemon shuts down regardless of any running queries. 3600 600 false
shutdown_grace_period_s (int64) Shutdown startup grace period in seconds. When the shutdown process is started for this daemon, it will wait for at least the startup grace period before shutting down. This gives time for updated cluster membership information to propagate to all coordinators and for fragment instances that were scheduled based on old cluster membership to start executing (and therefore be reflected in the metrics used to detect quiescence). 120 60 false
slow_profile_dump_warning_threshold_ms (int64) (Advanced) Threshold for considering dumping a profile to be unusually slow. 500 500 false
ssl_cipher_list (string) The cipher suite preferences to use for TLS-secured Thrift RPC connections. Uses the OpenSSL cipher preference list format. See man (1) ciphers for more information. If empty, the default cipher list for your platform is used ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:AES256-GCM-SHA384:AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256:AES256-SHA:AES128-SHA ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDH-ECDSA-AES256-SHA384:ECDH-RSA-AES256-GCM-SHA384:ECDH-ECDSA-AES256-GCM-SHA384:ECDH-RSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDH-ECDSA-AES128-SHA256:ECDH-RSA-AES128-GCM-SHA256:ECDH-ECDSA-AES128-GCM-SHA256:ECDH-RSA-AES128-SHA256 false
ssl_client_ca_certificate (string) (Advanced) The full path to a certificate used by Thrift clients to check the validity of a server certificate. May either be a certificate for a third-party Certificate Authority, or a copy of the certificate the client expects to receive from the server. /opt/impala/tls/ca.crt false
ssl_minimum_version (string) The minimum SSL/TLS version that Thrift services should use for both client and server connections. Supported versions are TLSv1.0, TLSv1.1 and TLSv1.2 (as long as the system OpenSSL library supports them) tlsv1.2 tlsv1.2 false
ssl_private_key (string) The full path to the private key used as a counterpart to the public key contained in --ssl_server_certificate. If --ssl_server_certificate is set, this option must be set as well. /opt/impala/tls/server.key false
ssl_private_key_password_cmd (string) A Unix command whose output returns the password used to decrypt the certificate private key file specified in --ssl_private_key. If the .PEM key file is not password-protected, this command will not be invoked. The output of the command will be truncated to 1024 bytes, and then all trailing whitespace will be trimmed before it is used to decrypt the private key false
ssl_server_certificate (string) The full path to the SSL certificate file used to authenticate Impala to clients. If set, both Beeswax and HiveServer2 ports will only accept SSL connections /opt/impala/tls/server.crt false
status_report_cancellation_padding (int32) (Advanced) The coordinator will wait --status_report_max_retry_s * (1 + --status_report_cancellation_padding / 100) without receiving a status report before deciding that a backend is unresponsive and the query should be cancelled. This must be > 0. 20 20 false
status_report_interval_ms (int32) (Advanced) Interval between profile reports in milliseconds. If set to <= 0, periodic reporting is disabled and only the final report is sent. 5000 5000 false
status_report_max_retry_s (int32) (Advanced) Max amount of time in seconds for a backend to attempt to send a status report before cancelling. This must be > --status_report_interval_ms. Effective only if --status_report_interval_ms > 0. 600 600 false
tls_ciphersuites (string) The TLSv1.3 cipher suites to use for TLS-secured Thrift RPC and KRPC connections. TLSv1.3 uses a new way to specify ciper suites that is independent of the older TLSv1.2 and below cipher lists. See 'man (1) ciphers' for more information. This flag is only effective if Impala is built with OpenSSL v1.1.1 or newer. TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256 false
unregistration_thread_pool_queue_depth (int32) (Advanced) Max number of queries that can be queued for unregistration. 16 16 false
unregistration_thread_pool_size (int32) (Advanced) Size of the thread-pool for unregistering queries, including finalizing runtime profiles 4 4 false
use_local_tz_for_unix_timestamp_conversions (bool) When true, TIMESTAMPs are interpreted in the local time zone when converting to and from Unix times. When false, TIMESTAMPs are interpreted in the UTC time zone. Set to true for Hive compatibility. Can be overriden with the query option with the same name. false false false
wait_for_new_catalog_service_id_max_iterations (int32) This flag is used in the same situation as described at the '--wait_for_new_catalog_service_id_timeout_sec' flag. Instead of limiting the waiting time, the effect of this flag is that the coordinator gives up waiting after receiving the set number of valid catalog updates that do not change the catalog service ID. Negative values and zero have no effect. If both this flag and '--wait_for_new_catalog_service_id_timeout_sec' are set, the coordinator stops waiting when the stop condition of either of them is met. Note that it is possible that the coordinator does not receive any catalog update from the statestore and in this case it will wait indefinitely if '--wait_for_new_catalog_service_id_timeout_sec' is not set. 10 10 false
wait_for_new_catalog_service_id_timeout_sec (int32) During DDL/DML queries, if there is a mismatch between the catalog service ID thatthe coordinator knows of and the one in the RPC response from the catalogd, the coordinator waits for a statestore update with a new catalog service ID in order to catch up with the one in the RPC response. However, in rare cases the service ID the coordinator knows of is the more recent one, in which case it could wait infinitely - to avoid this, this flag can be set to a positive value (in seconds) to limit the waiting time. Negative values and zero have no effect. See also '--wait_for_new_catalog_service_id_max_iterations,'. 300 300 false
cluster_id (string) Specifies an identifier string that uniquely represents this cluster. This identifier is included in the query log table if enabled. false
enable_workload_mgmt (bool) Specifies if Impala will automatically write completed queries in the query log table. If this value is set to true and then later removed, the query log table will remain intact and accessible. false false false
query_log_max_plan_length (int32) Maximum length of the sql plan that will be recorded in the completed queries table. If a plan has a length longer than this value, the plan inserted into the completed queries table will be trimmed to this length. Any characters that need escaping will have their backslash character counted towards this limit. 16777216 16777216 false
query_log_max_queued (int32) Maximum number of records that can be queued before they are written to the impala query log table. This flag operates independently of the 'query_log_write_interval_s' flag. If the number of queued records reaches this value, the records will be written to the query log table no matter how much time has passed since the last write. The countdown to the next write (based on the time period defined in the 'query_log_write_interval_s' flag) is not restarted. 5000 5000 false
query_log_max_sql_length (int32) Maximum length of a sql statement that will be recorded in the completed queries table. If a sql statement with a length longer than this value is executed, the sql inserted into the completed queries table will be trimmed to this length. Any characters that need escaping will have their backslash character counted towards this limit. 16777216 16777216 false
query_log_request_pool (string) Specifies a pool or queue used by the queries that insert into the query log table. Empty value causes no pool to be set. false
query_log_write_interval_s (int32) Number of seconds to wait between batches of inserts to the query log table. The countdown to the next write starts immediately when a write begins, but a new write will not start until the prior write has completed. Min value is 1. Max value is 14400. 300 300 false
enable_ha_statestore_k8s_lease_name (string) Name of the K8s lease for leader election impala-statestore-lease impala-statestore-lease false
enable_ha_statestore_k8s_lease_namespace (string) Namespace for the K8s lease default default false
enable_ha_statestore_k8s_lease_renew_interval_ms (int32) Interval in milliseconds for lease renewal attempts 5000 5000 false
statestore_client_rpc_timeout_ms (int32) (Advanced) The underlying TSocket send/recv timeout in milliseconds for a catalog client RPC. 300000 300000 false
statestore_subscriber_cnxn_attempts (int32) The number of times to retry an RPC connection to the statestore. A setting of 0 means retry indefinitely 10 10 false
statestore_subscriber_cnxn_retry_interval_ms (int32) The interval, in ms, to wait between attempts to make an RPC connection to the statestore. 3000 3000 false
statestore_subscriber_timeout_seconds (int32) The amount of time (in seconds) that may elapse before the connection with the statestore is considered lost. 30 30 false
statestore_subscriber_use_resolved_address (bool) If set to true, the subscriber will register with statestore using its resolved IP address. Note that using resolved IP address may cause mismatch with the TLS certificate. false false false
enable_ha_statestore_k8s_lease_election (bool) Enable K8s lease-based leader election instead of built-in HA mechanism true true false
enable_statestored_ha (bool) Set to true to enable Statestore HA false false false
state_store_peer_ha_port (int32) port where peer's StatestoreHaService is running 24021 24021 false
state_store_peer_host (string) hostname where peer's StatestoreHaService is running localhost localhost false
statestore_force_active (bool) Set to true to force this statestored instance to take active role. It's used to perform manual fail over for statestore service. false false false
statestore_ha_client_rpc_timeout_ms (int32) (Advanced) The underlying TSocket send/recv timeout in milliseconds for a client RPC of Statestore HA service. 300000 300000 false
statestore_ha_preemption_wait_period_ms (int64) (Advanced) The time after which statestored designates itself as active role if the statestore does not receive HA handshake request/response from peer statestored. 10000 10000 false
statestore_heartbeat_frequency_ms (int32) (Advanced) Frequency (in ms) with which the statestore sends heartbeat heartbeats to subscribers. 1000 1000 false
statestore_heartbeat_tcp_timeout_seconds (int32) (Advanced) The time after which a heartbeat RPC to a subscriber will timeout. This setting protects against badly hung machines that are not able to respond to the heartbeat RPC in short order 3 3 false
statestore_max_missed_heartbeats (int32) Maximum number of consecutive heartbeat messages an impalad can miss before being declared failed by the statestore. 10 10 false
statestore_max_subscribers (int32) Used to control the maximum size of the pending topic-update queue. There is at most one entry per subscriber. 10000 10000 false
statestore_num_heartbeat_threads (int32) (Advanced) Number of threads used to send heartbeats in parallel to all registered subscribers. 10 10 false
statestore_num_priority_update_threads (int32) (Advanced) Number of threads used to send prioritized topic updates in parallel to all registered subscribers. 10 10 false
statestore_num_update_threads (int32) (Advanced) Number of threads used to send topic updates in parallel to all registered subscribers. 10 10 false
statestore_peer_cnxn_attempts (int32) The number of times to retry an RPC connection to the peer statestore. A setting of 0 means retry indefinitely 10 10 false
statestore_peer_cnxn_retry_interval_ms (int32) The interval, in ms, to wait between attempts to make an RPC connection to the peer statestore. It's set as statestore_ha_preemption_wait_period_ms/statestore_peer_cnxn_attempts if statestore_peer_cnxn_attempts > 0, default value if statestore_peer_cnxn_attempts == 0. 1000 1000 false
statestore_peer_timeout_seconds (int32) The amount of time (in seconds) that may elapse before the connection with the peer statestore is considered lost. 30 30 false
statestore_priority_update_frequency_ms (int32) (Advanced) Frequency (in ms) with which the statestore sends prioritized topic updates to subscribers. 100 100 false
statestore_update_catalogd_tcp_timeout_seconds (int32) (Advanced) The time after which a UpdateCatalogd RPC to a subscriber will timeout. This setting protects against badly hung machines that are not able to respond to the UpdateCatalogd RPC in short order 3 3 false
statestore_update_frequency_ms (int32) (Advanced) Frequency (in ms) with which the statestore sends topic updates to subscribers. 2000 2000 false
statestore_update_statestore_tcp_timeout_seconds (int32) (Advanced) The time after which a UpdateStatestoredRole RPC to a subscriber will timeout. This setting protects against badly hung machines that are not able to respond to the UpdateStatestoredRole RPC in short order. 3 3 false
statestore_update_tcp_timeout_seconds (int32) (Advanced) The time after which an update RPC to a subscriber will timeout. This setting protects against badly hung machines that are not able to respond to the update RPC in short order. 300 300 false
update_statestore_rpc_resend_interval_ms (int64) (Advanced) Interval (in ms) with which the statestore resends the RPCs of updating statestored's role to subscribers if the statestore has failed to send the RPCs to the subscribers. 100 100 false
use_network_address_as_statestore_priority (bool) Network address is used as priority value of statestored instance if this is set as true. Otherwise, statestored_id which is generated as random number will be used as priority value of statestored instance. false false false
force_lowercase_usernames (bool) If true, all principals and usernames are mapped to lowercase shortnames before being passed to any components (Ranger, admission control) for authorization false false false
sasl_connect_tcp_timeout_ms (int32) (Advanced) The underlying TSocket send/recv timeout in milliseconds for the initial SASL handeshake. 300000 300000 false
allow_ordinals_in_having (bool) If true, allow using ordinals in HAVING clause. This non-standard feature is supported in Impala 3.x and earlier. We intend to disable it since 4.0. So it defaults to be false. See IMPALA-7844. false false false
enable_column_masking (bool) If false, disable the column masking feature. Defaults to be true. true true false
enable_row_filtering (bool) If false, disable the row filtering feature. Defaults to be true. Enabling this flag requires enable_column_masking to be true. true true false
ignored_dir_prefix_list (string) Comma separated list to specify the prefix for tmp/staging dirs that catalogd should skip in loading file metadata. .,_tmp.,_spark_metadata .,_tmp.,_spark_metadata false
saml2_callback_token_ttl (int32) Time (in milliseconds) for which the token issued by service provider is valid. 30000 30000 false
saml2_group_attribute_name (string) The attribute name in the SAML assertion which would be used to compare for the group name matching. By default it is empty which would allow any authenticated user. If this value is set then saml2_group_filter must be set to a non-empty value. false
saml2_group_filter (string) Comma separated list of group names which will be allowed when SAML authentication is enabled. false
saml2_idp_metadata (string) IDP metadata file for the SAML configuration. This metadata file must be exported from the external identity provider. This is used to validate the SAML assertions received. Setting this is required for SAML authentication false
saml2_keystore_password_cmd (string) Command that outputs the password to the keystore used to sign the authentication requests. Setting this is required for SAML authentication. <redacted> false
saml2_keystore_path (string) Keystore path to the saml2 client. This keystore is used to store the key pair used to sign the authentication requests when saml2_sign_requests is set to true. If the path doesn't exist, HiveServer2 will attempt to create a keystore using the default configurations otherwise it will use the one provided. Setting this is required for SAML authentication. false
saml2_private_key_password_cmd (string) Command that outputs the password for the private key which is stored in the keystore pointed by saml2_keystore_path. This key is used to sign the authentication request if saml2_sign_requests is set to true. <redacted> false
saml2_sign_requests (bool) When this configuration is set to true, Impala will sign the SAML requests which can be validated by the IDP provider. false false false
saml2_sp_callback_url (string) Callback URL where SAML responses should be posted. Currently this must be configured at the same port number as the --hs2_http_port flag. false
saml2_sp_entity_id (string) Service provider entity id for this impalad. This must match with the SP id on the external identity provider. If this is not set, saml2_sp_callback_url will be used as the SP id. false
saml2_want_assertations_signed (bool) When this configuration is set to true, Impala will validate the signature of the assertions received at the callback url. 'False' should be only used for testing as it makes the protocol unsecure. true true false
startup_filesystem_check_directories (string) Comma separated list of directories to list on startup to verify access to the filesystem. The default is to list the root of the filesytem. This can be specified to a subdirectory to avoid accesses to the root of the filesystem. To disable the startup check, specify the empty string. / / false
use_hms_column_order_for_hbase_tables (bool) Use the column order in HMS for HBase tables instead of ordering the columns by family/qualifier. Keeping the default as false for backward compatibility. false false false
warn_catalog_response_duration_s (int32) Threshold in seconds to log a warning for slow catalogd response. 60 60 false
warn_catalog_response_size_mb (int32) Threshold in MB to log a warning for large catalogd response size. 50 50 false
num_cores (int32) (Advanced) If > 0, it sets the number of cores available to Impala. Setting it to 0 means Impala will use all available cores on the machine according to /proc/cpuinfo. 0 0 false
web_log_bytes (int64) The maximum number of bytes to display on the debug webserver's log page 1048576 1048576 false
jvm_deadlock_detector_interval_s (int64) (Advanced) Interval between JVM deadlock checks. If set to 0 or a negative value, deadlock checks are disabled. 60 60 false
ldap_group_search_basedn (string) The 'distinguished name' DN that will be used to search for the authenticating group. If left empty, group checks will not be performed. false
ldap_user_search_basedn (string) The 'distinguished name' DN that will be used to search for the authenticating user, this field is required for search bind authentication. dc=example,dc=org false
ldap_baseDN (string) If set, Impala will try to bind to LDAP with a name of the form uid=<userid>,<ldap_baseDN> false
ldap_bind_pattern (string) If set, Impala will try to bind to LDAP with a name of <ldap_bind_pattern>, but where the string #UID is replaced by the user ID. Use to control the bind name precisely; do not set --ldap_domain or --ldap_baseDN with this option false
ldap_domain (string) If set, Impala will try to bind to LDAP with a name of the form <userid>@<ldap_domain> false
ldap_group_class_key (string) The LDAP objectClass each of the groups in --ldap_group_filter implements in LDAP. groupOfNames groupOfNames false
ldap_group_dn_pattern (string) Colon separated list of patterns for the 'distinguished name' used to search for groups in the directory. Each pattern may contain a '%s' which will be substituted with each group name from --ldap_group_filter when doing group searches. false
ldap_group_membership_key (string) The LDAP attribute on group entries that indicates its members. member member false
allow_custom_ldap_filters_with_kerberos_auth (bool) If set, will allow custom LDAP user and group filters even if Kerberos authentication is enabled. Disabled by default. false false false
ldap_allow_anonymous_binds (bool) (Advanced) If true, LDAP authentication with a blank password (an 'anonymous bind') is allowed by Impala. false false false
ldap_bind_dn (string) Distinguished name of the user to bind as when doing user or group searches. Only required if user or group filters are being used and the LDAP server is not configured to allow anonymous searches. cn=readonly,dc=example,dc=org false
ldap_bind_password_cmd (string) A Unix command whose output returns the password to use with --ldap_bind_dn. The output of the command will be truncated to 1024 bytes and trimmed of trailing whitespace. <redacted> false
ldap_passwords_in_clear_ok (bool) If set, will allow LDAP passwords to be sent in the clear (without TLS/SSL) over the network. This option should not be used in production environments false false false
ldap_referral (bool) set LDAP_OPT_REFERRALS false false false
ldap_search_bind_authentication (bool) If set to true, LDAP search bind authentication will be used instead of the default simple bind. false true false
ldap_tls (bool) If true, use the secure TLS protocol to connect to the LDAP server false true false
ldap_uri (string) The URI of the LDAP server to authenticate users against ldaps://openldap.openldap:636 false
non_impala_java_vlog (int32) (Advanced) The log level (equivalent to --v) for non-Impala Java classes (0: INFO, 1 and 2: DEBUG, 3: TRACE) 0 0 false
disable_parquetbloomfilter_avx2 (bool) Disable AVX2 operations in ParquetBloomFilter. This flag has no effect if the target CPU doesn't support AVX2 at run-time or ParquetBloomFilter was built with a compiler that doesn't support AVX2. false false false
periodic_counter_update_period_ms (int32) Period to update query profile rate counters and sampling counters in ms 50 50 false
periodic_system_counter_update_period_ms (int32) Period to update system-level rate counters and sampling counters in ms 500 500 false
disable_content_security_policy_header (bool) If true then the webserver will not add the Content-Security-Policy HTTP header to HTTP responses false false false
enable_webserver_doc_root (bool) If true, webserver may serve static files from the webserver_doc_root true true false
slow_http_response_warning_threshold_ms (int64) (Advanced) Threshold for considering a HTTP response to be unusually slow. 500 500 false
webserver_authentication_domain (string) Domain used for debug webserver authentication false
webserver_certificate_file (string) The location of the debug webserver's SSL certificate file, in .pem format. If empty, webserver SSL support is not enabled /opt/impala/runtime/chain.pem false
webserver_doc_root (string) Files under <webserver_doc_root>/www are accessible via the debug webserver. Defaults to $IMPALA_HOME, or if $IMPALA_HOME is not set, disables the document root /opt/impala /opt/impala false
webserver_interface (string) Interface to start debug webserver on. If blank, webserver binds to 0.0.0.0 false
webserver_ldap_group_filter (string) Used as filter for both simple and search bind mechanisms for the webserver authentication. For simple bind it is a comma separated list of groups. If specified, users must belong to one of these groups for authentication to succeed. For search bind it is an LDAP filter that will be used during LDAP group search, it can contain '{0}' pattern which will be replaced with the user name and/or '{1}' which will be replace with the user dn. false
webserver_ldap_passwords_in_clear_ok (bool) (Advanced) If true, allows the webserver to start with LDAP authentication even if SSL is not enabled, a potentially insecure configuration. false false false
webserver_ldap_user_filter (string) Used as filter for both simple and search bind mechanisms for the webserver authentication. For simple bind it is a comma separated list of user names. If specified, users must be on this list for authentication to succeed. For search bind it is an LDAP filter that will be used during LDAP search, it can contain '{0}' pattern which will be replaced with the user name. false
webserver_max_post_length_bytes (int32) The maximum length of a POST request that will be accepted by the embedded web server. 1048576 1048576 false
webserver_password_file (string) (Optional) Location of .htpasswd file containing user names and hashed passwords for debug webserver authentication. Cannot be used with --webserver_require_ldap or --webserver_require_spnego. false
webserver_port (int32) Port to start debug webserver on 25000 25000 false
webserver_private_key_file (string) The full path to the private key used as a counterpart to the public key contained in --webserver_certificate_file. If --webserver_certificate_file is set, this option must be set as well. false
webserver_private_key_password_cmd (string) A Unix command whose output returns the password used to decrypt the Webserver's certificate private key file specified in --webserver_private_key_file. If the .PEM key file is not password-protected, this command will not be invoked. The output of the command will be truncated to 1024 bytes, and then all trailing whitespace will be trimmed before it is used to decrypt the private key false
webserver_require_ldap (bool) Require connections to the web server to authenticate via LDAP using HTTP Basic authentication. Cannot be used with --webserver_require_spnego or --webserver_password_file. false false false
webserver_require_spnego (bool) Require connections to the web server to authenticate via Kerberos using SPNEGO. Cannot be used with --webserver_require_ldap or --webserver_password_file. false false false
webserver_x_frame_options (string) webserver will add X-Frame-Options HTTP header with this value DENY DENY false
flagfile (string) load flags from file /opt/impala/conf/impala.flags false
fromenv (string) set flags from the environment [use 'export FLAGS_flag1=value'] false
tryfromenv (string) set flags from the environment if present false
undefok (string) comma-separated list of flag names that it is okay to specify on the command line even if the program does not define a flag with that name. IMPORTANT: flags in this list that have arguments MUST use the flag=value format false
tab_completion_columns (int32) Number of columns to use in output for tab completion 80 80 false
tab_completion_word (string) If non-empty, HandleCommandLineCompletions() will hijack the process and attempt to do bash-style command line flag completion on this value. false
help (bool) show help on all flags [tip: all flags can have two dashes] false false false
helpfull (bool) show help on all flags -- same as -help false false false
helpmatch (string) show help on modules whose name contains the specified substr false
helpon (string) show help on the modules named by this flag value false
helppackage (bool) show help on all modules in the main package false false false
helpshort (bool) show help on only the main module for this program false false false
helpxml (bool) produce an xml version of help false false false
version (bool) show version and build info and exit false false false
alsologtoemail (string) log messages go to these email addresses in addition to logfiles false
alsologtostderr (bool) log messages go to stderr in addition to logfiles false false false
colorlogtostderr (bool) color messages logged to stderr (if supported by terminal) false false false
drop_log_memory (bool) Drop in-memory buffers of log contents. Logs can grow very quickly and they are rarely read before they need to be evicted from memory. Instead, drop them from memory as soon as they are flushed to disk. true true false
log_backtrace_at (string) Emit a backtrace when logging at file:linenum. false
log_dir (string) If specified, logfiles are written into this directory instead of the default logging directory. /opt/impala/logs false
log_link (string) Put additional links to the log files in this directory false
log_prefix (bool) Prepend the log prefix to the start of each log line true true false
logbuflevel (int32) Buffer log messages logged at this level or lower (-1 means don't buffer; 0 means buffer INFO only; ...) 0 0 false
logbufsecs (int32) Buffer log messages for at most this many seconds 30 30 false
logemaillevel (int32) Email log messages logged at this level or higher (0 means email all; 3 means email FATAL only; ...) 999 999 false
logfile_mode (int32) Log file mode/permissions. 436 436 false
logmailer (string) Mailer used to send logging email /bin/mail /bin/mail false
logtostderr (bool) log messages go to stderr instead of logfiles false false false
max_log_size (int32) approx. maximum log file size (in MB). A value of 0 will be silently overridden to 1. 1800 200 false
minloglevel (int32) Messages logged at a lower level than this don't actually get logged anywhere 0 0 false
stderrthreshold (int32) log messages at or above this level are copied to stderr in addition to logfiles. This flag obsoletes --alsologtostderr. 2 4 false
stop_logging_if_full_disk (bool) Stop attempting to log to disk if the disk is full. false false false
symbolize_stacktrace (bool) Symbolize the stack trace in the tombstone true false false
v (int32) Show all VLOG(m) messages for m <= this. Overridable by --vmodule. 0 0 false
vmodule (string) per-module verbose level. Argument is a comma-separated list of <module name>=<log level>. <module name> is a glob pattern, matched against the filename base (that is, name ignoring .cc/.h./-inl.h). <log level> overrides any value given by --v. false