Aurora MySQL configuration parameters

You manage your Amazon Aurora MySQL DB cluster in the same way that you manage other Amazon RDS DB instances, by using parameters in a DB parameter group. Amazon Aurora differs from other DB engines in that you have a DB cluster that contains multiple DB instances. As a result, some of the parameters that you use to manage your Aurora MySQL DB cluster apply to the entire cluster. Other parameters apply only to a particular DB instance in the DB cluster.

To manage cluster-level parameters, use DB cluster parameter groups. To manage instance-level parameters, use DB parameter groups. Each DB instance in an Aurora MySQL DB cluster is compatible with the MySQL database engine. However, you apply some of the MySQL database engine parameters at the cluster level, and you manage these parameters using DB cluster parameter groups. You can't find cluster-level parameters in the DB parameter group for an instance in an Aurora DB cluster. A list of cluster-level parameters appears later in this topic.

You can manage both cluster-level and instance-level parameters using the AWS Management Console, the AWS CLI, or the Amazon RDS API. You use separate commands for managing cluster-level parameters and instance-level parameters. For example, you can use the modify-db-cluster-parameter-group CLI command to manage cluster-level parameters in a DB cluster parameter group. You can use the modify-db-parameter-group CLI command to manage instance-level parameters in a DB parameter group for a DB instance in a DB cluster.

You can view both cluster-level and instance-level parameters in the console, or by using the CLI or RDS API. For example, you can use the describe-db-cluster-parameters AWS CLI command to view cluster-level parameters in a DB cluster parameter group. You can use the describe-db-parameters CLI command to view instance-level parameters in a DB parameter group for a DB instance in a DB cluster.

Note

Each default parameter group contains the default values for all parameters in the parameter group. If the parameter has "engine default" for this value, see the version-specific MySQL or PostgreSQL documentation for the actual default value.

Unless otherwise noted, parameters listed in the following tables are valid for Aurora MySQL versions 2 and 3.

For more information about DB parameter groups, see Parameter groups for Amazon Aurora. For rules and restrictions for Aurora Serverless v1 clusters, see Parameter groups for Aurora Serverless v1.

Cluster-level parameters

The following table shows all of the parameters that apply to the entire Aurora MySQL DB cluster.

Parameter name	Modifiable	Notes
aurora_binlog_read_buffer_size	Yes	Only affects clusters that use binary log (binlog) replication. For information about binlog replication, see Replication between Aurora and MySQL or between Aurora and another Aurora DB cluster (binary log replication). Removed from Aurora MySQL version 3.
aurora_binlog_replication_max_yield_seconds	Yes	Only affects clusters that use binary log (binlog) replication. For information about binlog replication, see Replication between Aurora and MySQL or between Aurora and another Aurora DB cluster (binary log replication).
aurora_binlog_replication_sec_index_parallel_workers	Yes	Sets the total number of parallel threads available to apply secondary index changes when replicating transactions for large tables with more than one secondary index. The parameter is set to 0 (disabled) by default. This parameter is available in Aurora MySQL version 306 and higher. For more information, see Optimizing binary log replication for Aurora MySQL.
aurora_binlog_use_large_read_buffer	Yes	Only affects clusters that use binary log (binlog) replication. For information about binlog replication, see Replication between Aurora and MySQL or between Aurora and another Aurora DB cluster (binary log replication). Removed from Aurora MySQL version 3.
aurora_disable_hash_join	Yes	Set this parameter to ON to turn off hash join optimization in Aurora MySQL version 2.09 or higher. It isn't supported for version 3. For more information, see Parallel query for Amazon Aurora MySQL.
aurora_enable_replica_log_compression	Yes	For more information, see Performance considerations for Amazon Aurora MySQL replication. Doesn't apply to clusters that are part of an Aurora global database. Removed from Aurora MySQL version 3.
aurora_enable_repl_bin_log_filtering	Yes	For more information, see Performance considerations for Amazon Aurora MySQL replication. Doesn't apply to clusters that are part of an Aurora global database. Removed from Aurora MySQL version 3.
aurora_enable_staggered_replica_restart	Yes	This setting is available in Aurora MySQL version 3, but it isn't used.
aurora_enable_zdr	Yes	This setting is turned on by default in Aurora MySQL 2.10 and higher. For more information, see Zero-downtime restart (ZDR) for Amazon Aurora MySQL.
aurora_enhanced_binlog	Yes	Set the value of this parameter to 1 to turn on the enhanced binlog in Aurora MySQL version 3.03.1 and higher. For more information, see Setting up enhanced binlog for Aurora MySQL.
aurora_full_double_precision_in_json	Yes	Set the value of this parameter to enable the parsing of floating point numbers in JSON documents with full precision.
aurora_jemalloc_background_thread	Yes	Use this parameter to enable a background thread to perform memory maintenance operations. The allowed values are 0 (disabled) and 1 (enabled). The default value is 0. This parameter applies to Aurora MySQL version 3.05 and higher.
aurora_jemalloc_dirty_decay_ms	Yes	Use this parameter to retain freed memory for a certain amount of time (in milliseconds). Retaining memory allows for faster reuse. The allowed values are 0–18446744073709551615. The default value is 10000 (10 seconds). You can use a shorter delay to help avoid out-of-memory issues, at the expense of slower performance. This parameter applies to Aurora MySQL version 3.05 and higher.
aurora_jemalloc_tcache_enabled	Yes	Use this parameter to serve small memory requests (up to 32 KiB) in a thread local cache, bypassing the memory arenas. The allowed values are 0 (disabled) and 1 (enabled). The default value is 1. This parameter applies to Aurora MySQL version 3.05 and higher.
aurora_load_from_s3_role	Yes	For more information, see Loading data into an Amazon Aurora MySQL DB cluster from text files in an Amazon S3 bucket. Currently not available in Aurora MySQL version 3. Use aws_default_s3_role.
aurora_mask_password_hashes_type	Yes	This setting is turned on by default in Aurora MySQL 2.11 and higher. Use this setting to mask Aurora MySQL password hashes in the slow query and audit logs. The allowed values are 0 and 1 (default). When set to 1, passwords are logged as <secret>. When set to 0, passwords are logged as hash (#) values.
aurora_select_into_s3_role	Yes	For more information, see Saving data from an Amazon Aurora MySQL DB cluster into text files in an Amazon S3 bucket. Currently not available in Aurora MySQL version 3. Use aws_default_s3_role.
authentication_kerberos_caseins_cmp	Yes	Controls case-insensitive username comparison for the authentication_kerberos plugin. Set it to true for case-insensitive comparison. By default, case-sensitive comparison is used (false). For more information, see Using Kerberos authentication for Aurora MySQL. This parameter is available in Aurora MySQL version 3.03 and higher.
auto_increment_increment	Yes
auto_increment_offset	Yes
aws_default_lambda_role	Yes	For more information, see Invoking a Lambda function from an Amazon Aurora MySQL DB cluster.
aws_default_s3_role	Yes	Used when invoking the LOAD DATA FROM S3, LOAD XML FROM S3, or SELECT INTO OUTFILE S3 statement from your DB cluster. In Aurora MySQL version 2, the IAM role specified in this parameter is used if an IAM role isn't specified for aurora_load_from_s3_role or aurora_select_into_s3_role for the appropriate statement. In Aurora MySQL version 3, the IAM role specified for this parameter is always used. For more information, see Associating an IAM role with an Amazon Aurora MySQL DB cluster.
binlog_backup	Yes	Set the value of this parameter to 0 to turn on the enhanced binlog in Aurora MySQL version 3.03.1 and higher. You can turn off this parameter only when you use enhanced binlog. For more information, see Setting up enhanced binlog for Aurora MySQL.
binlog_checksum	Yes	The AWS CLI and RDS API report a value of None if this parameter isn't set. In that case, Aurora MySQL uses the engine default value, which is CRC32. This is different from the explicit setting of NONE, which turns off the checksum.
binlog-do-db	Yes	This parameter applies to Aurora MySQL version 3.
binlog_format	Yes	For more information, see Replication between Aurora and MySQL or between Aurora and another Aurora DB cluster (binary log replication).
binlog_group_commit_sync_delay	Yes	This parameter applies to Aurora MySQL version 3.
binlog_group_commit_sync_no_delay_count	Yes	This parameter applies to Aurora MySQL version 3.
binlog-ignore-db	Yes	This parameter applies to Aurora MySQL version 3.
binlog_replication_globaldb	Yes	Set the value of this parameter to 0 to turn on the enhanced binlog in Aurora MySQL version 3.03.1 and higher. You can turn off this parameter only when you use enhanced binlog. For more information, see Setting up enhanced binlog for Aurora MySQL.
binlog_row_image	No
binlog_row_metadata	Yes	This parameter applies to Aurora MySQL version 3.
binlog_row_value_options	Yes	This parameter applies to Aurora MySQL version 3.
binlog_rows_query_log_events	Yes
binlog_transaction_compression	Yes	This parameter applies to Aurora MySQL version 3.
binlog_transaction_compression_level_zstd	Yes	This parameter applies to Aurora MySQL version 3.
binlog_transaction_dependency_history_size	Yes	This parameter sets an upper limit on the number of row hashes that are kept in memory and used for looking up the transaction that last modified a given row. After this number of hashes has been reached, the history is purged. This parameter applies to Aurora MySQL version 2.12 and higher, and version 3.
binlog_transaction_dependency_tracking	Yes	This parameter applies to Aurora MySQL version 3.
character-set-client-handshake	Yes
character_set_client	Yes
character_set_connection	Yes
character_set_database	Yes	The character set used by the default database. The default value is utf8mb4.
character_set_filesystem	Yes
character_set_results	Yes
character_set_server	Yes
collation_connection	Yes
collation_server	Yes
completion_type	Yes
default_storage_engine	No	Aurora MySQL clusters use the InnoDB storage engine for all of your data.
enforce_gtid_consistency	Sometimes	Modifiable in Aurora MySQL version 2 and higher.
event_scheduler	Yes	Indicates the status of the Event Scheduler. Modifiable only at the cluster level in Aurora MySQL version 3.
gtid-mode	Sometimes	Modifiable in Aurora MySQL version 2 and higher.
information_schema_stats_expiry	Yes	The number of seconds after which the MySQL database server fetches data from the storage engine and replaces the data in the cache. The allowed values are 0–31536000. This parameter applies to Aurora MySQL version 3.
init_connect	Yes	The command to be run by the server for each client that connects. Use double quotes (") for settings to avoid connection failures, for example: SET optimizer_switch="hash_join=off" In Aurora MySQL version 3, this parameter doesn't apply for users who have the CONNECTION_ADMIN privilege. This includes the Aurora master user. For more information, see Role-based privilege model.
innodb_adaptive_hash_index	Yes	You can modify this parameter at the DB cluster level in Aurora MySQL versions 2 and 3. The Adaptive Hash Index isn't supported on reader DB instances.
innodb_aurora_instant_alter_column_allowed	Yes	Controls whether the INSTANT algorithm can be used for ALTER COLUMN operations at the global level. The allowed values are the following: 0 – The INSTANT algorithm isn't allowed for ALTER COLUMN operations (OFF). Reverts to other algorithms. 1 – The INSTANT algorithm is allowed for ALTER COLUMN operations (ON). This is the default value. For more information, see Column Operations in the MySQL documentation. This parameter applies to Aurora MySQL version 3.05 and higher.
innodb_autoinc_lock_mode	Yes
innodb_checksums	No	Removed from Aurora MySQL version 3.
innodb_cmp_per_index_enabled	Yes
innodb_commit_concurrency	Yes
innodb_data_home_dir	No	Aurora MySQL uses managed instances where you don't access the file system directly.
innodb_deadlock_detect	Yes	This option is used to disable deadlock detection in Aurora MySQL version 2.11 and higher and version 3. On high-concurrency systems, deadlock detection can cause a slowdown when numerous threads wait for the same lock. Consult the MySQL documentation for more information on this parameter.
innodb_default_row_format	Yes	This parameter defines the default row format for InnoDB tables (including user-created InnoDB temporary tables). It applies to Aurora MySQL versions 2 and 3. Its value can be DYNAMIC, COMPACT, or REDUNDANT.
innodb_file_per_table	Yes	This parameter affects how table storage is organized. For more information, see Storage scaling.
innodb_flush_log_at_trx_commit	Yes	We highly recommend that you use the default value of 1. In Aurora MySQL version 3, before you can set this parameter to a value other than 1, you must set the value of innodb_trx_commit_allow_data_loss to 1. For more information, see Configuring how frequently the log buffer is flushed.
innodb_ft_max_token_size	Yes
innodb_ft_min_token_size	Yes
innodb_ft_num_word_optimize	Yes
innodb_ft_sort_pll_degree	Yes
innodb_online_alter_log_max_size	Yes
innodb_optimize_fulltext_only	Yes
innodb_page_size	No
innodb_print_all_deadlocks	Yes	When turned on, records information about all InnoDB deadlocks in the Aurora MySQL error log. For more information, see Minimizing and troubleshooting Aurora MySQL deadlocks.
innodb_purge_batch_size	Yes
innodb_purge_threads	Yes
innodb_rollback_on_timeout	Yes
innodb_rollback_segments	Yes
innodb_spin_wait_delay	Yes
innodb_strict_mode	Yes
innodb_support_xa	Yes	Removed from Aurora MySQL version 3.
innodb_sync_array_size	Yes
innodb_sync_spin_loops	Yes
innodb_stats_include_delete_marked	Yes	When this parameter is enabled, InnoDB includes delete-marked records when calculating persistent optimizer statistics. This parameter applies to Aurora MySQL version 2.12 and higher, and version 3.
innodb_table_locks	Yes
innodb_trx_commit_allow_data_loss	Yes	In Aurora MySQL version 3, set the value of this parameter to 1 so that you can change the value of innodb_flush_log_at_trx_commit. The default value of innodb_trx_commit_allow_data_loss is 0. For more information, see Configuring how frequently the log buffer is flushed.
innodb_undo_directory	No	Aurora MySQL uses managed instances where you don't access the file system directly.
internal_tmp_disk_storage_engine	Yes	Controls which in-memory storage engine is used for internal temporary tables. Allowed values are INNODB and MYISAM. This parameter applies to Aurora MySQL version 2.
internal_tmp_mem_storage_engine	Yes	Controls which in-memory storage engine is used for internal temporary tables. Allowed values are MEMORY and TempTable. This parameter applies to Aurora MySQL version 3.
key_buffer_size	Yes	Key cache for MyISAM tables. For more information, see keycache->cache_lock mutex.
lc_time_names	Yes
log_error_suppression_list	Yes	Specifies a list of error codes that aren't logged in the MySQL error log. This allows you to ignore certain noncritical error conditions to help keep your error logs clean. For more information, see log_error_suppression_list in the MySQL documentation. This parameter applies to Aurora MySQL version 3.03 and higher.
low_priority_updates	Yes	INSERT, UPDATE, DELETE, and LOCK TABLE WRITE operations wait until there's no pending SELECT operation. This parameter affects only storage engines that use only table-level locking (MyISAM, MEMORY, MERGE). This parameter applies to Aurora MySQL version 3.
lower_case_table_names	Yes (Aurora MySQL version 2) Only at cluster creation time (Aurora MySQL version 3)	In Aurora MySQL version 2.10 and higher 2.x versions, make sure to reboot all reader instances after changing this setting and rebooting the writer instance. For details, see Rebooting an Aurora cluster with read availability. In Aurora MySQL version 3, the value of this parameter is set permanently at the time the cluster is created. If you use a nondefault value for this option, set up your Aurora MySQL version 3 custom parameter group before upgrading, and specify the parameter group during the snapshot restore operation that creates the version 3 cluster. With an Aurora global database based on Aurora MySQL, you can't perform an in-place upgrade from Aurora MySQL version 2 to version 3 if the lower_case_table_names parameter is turned on. For more information on the methods that you can use, see Major version upgrades.
master-info-repository	Yes	Removed from Aurora MySQL version 3.
master_verify_checksum	Yes	Aurora MySQL version 2. Use source_verify_checksum in Aurora MySQL version 3.
max_delayed_threads	Yes	Sets the maximum number of threads to handle INSERT DELAYED statements. This parameter applies to Aurora MySQL version 3.
max_error_count	Yes	The maximum number of error, warning, and note messages to be stored for display. This parameter applies to Aurora MySQL version 3.
max_execution_time	Yes	The timeout for running SELECT statements, in milliseconds. The value can be from 0–18446744073709551615. When set to 0, there is no timeout. For more information, see max_execution_time in the MySQL documentation.
min_examined_row_limit	Yes	Use this parameter to prevent queries that examine fewer than the specified number of rows from being logged.
partial_revokes	No	This parameter applies to Aurora MySQL version 3.
preload_buffer_size	Yes	The size of the buffer that's allocated when preloading indexes. This parameter applies to Aurora MySQL version 3.
query_cache_type	Yes	Removed from Aurora MySQL version 3.
read_only	Yes	When this parameter is turned on, the server permits no updates except from those performed by replica threads. For Aurora MySQL version 2, valid values are the following: 0 – OFF 1 – ON {TrueIfReplica} – ON for read replicas. This is the default value. {TrueIfClusterReplica} – ON for replica clusters such as cross-Region read replicas, secondary clusters in an Aurora global database, and blue/green deployments. For Aurora MySQL version 3, valid values are the following: 0 – OFF. This is the default value. 1 – ON {TrueIfClusterReplica} – ON for replica clusters such as cross-Region read replicas, secondary clusters in an Aurora global database, and blue/green deployments. In Aurora MySQL version 3, this parameter doesn't apply for users who have the CONNECTION_ADMIN privilege. This includes the Aurora master user. For more information, see Role-based privilege model.
relay-log-space-limit	Yes	This parameter applies to Aurora MySQL version 3.
replica_parallel_type	Yes	This parameter enables parallel execution on the replica of all uncommitted threads already in the prepare phase, without violating consistency. It applies to Aurora MySQL version 3. In Aurora MySQL version 3.03.* and lower, the default value is DATABASE. In Aurora MySQL version 3.04 and higher, the default value is LOGICAL_CLOCK.
replica_preserve_commit_order	Yes	This parameter applies to Aurora MySQL version 3.
replica_transaction_retries	Yes	This parameter applies to Aurora MySQL version 3.
replica_type_conversions	Yes	This parameter determines the type conversions used on replicas. The allowed values are: ALL_LOSSY, ALL_NON_LOSSY, ALL_SIGNED, and ALL_UNSIGNED. For more information, see Replication with differing table definitions on source and replica in the MySQL documentation. This parameter applies to Aurora MySQL version 3.
replicate-do-db	Yes	This parameter applies to Aurora MySQL version 3.
replicate-do-table	Yes	This parameter applies to Aurora MySQL version 3.
replicate-ignore-db	Yes	This parameter applies to Aurora MySQL version 3.
replicate-ignore-table	Yes	This parameter applies to Aurora MySQL version 3.
replicate-wild-do-table	Yes	This parameter applies to Aurora MySQL version 3.
replicate-wild-ignore-table	Yes	This parameter applies to Aurora MySQL version 3.
require_secure_transport	Yes	This parameter applies to Aurora MySQL version 2 and 3. For more information, see TLS connections to Aurora MySQL DB clusters.
rpl_read_size	Yes	This parameter applies to Aurora MySQL version 3.
server_audit_cw_upload	No	This parameter has been deprecated in Aurora MySQL. Use server_audit_logs_upload. For more information, see Publishing Amazon Aurora MySQL logs to Amazon CloudWatch Logs.
server_audit_events	Yes	For more information, see Using Advanced Auditing with an Amazon Aurora MySQL DB cluster.
server_audit_excl_users	Yes	For more information, see Using Advanced Auditing with an Amazon Aurora MySQL DB cluster.
server_audit_incl_users	Yes	For more information, see Using Advanced Auditing with an Amazon Aurora MySQL DB cluster.
server_audit_logging	Yes	For instructions on uploading the logs to Amazon CloudWatch Logs, see Publishing Amazon Aurora MySQL logs to Amazon CloudWatch Logs.
server_audit_logs_upload	Yes	You can publish audit logs to CloudWatch Logs by enabling Advanced Auditing and setting this parameter to 1. The default for the server_audit_logs_upload parameter is 0. For more information, see Publishing Amazon Aurora MySQL logs to Amazon CloudWatch Logs.
server_id	No
skip-character-set-client-handshake	Yes
skip_name_resolve	No
slave-skip-errors	Yes	Only applies to Aurora MySQL version 2 clusters, with MySQL 5.7 compatibility.
source_verify_checksum	Yes	This parameter applies to Aurora MySQL version 3.
sync_frm	Yes	Removed from Aurora MySQL version 3.
thread_cache_size	Yes	The number of threads to be cached. This parameter applies to Aurora MySQL versions 2 and 3.
time_zone	Yes	By default, the time zone for an Aurora DB cluster is Universal Time Coordinated (UTC). You can set the time zone for instances in your DB cluster to the local time zone for your application instead. For more information, see Local time zone for Amazon Aurora DB clusters.
tls_version	Yes	For more information, see TLS versions for Aurora MySQL.

Instance-level parameters

The following table shows all of the parameters that apply to a specific DB instance in an Aurora MySQL DB cluster.

Parameter name	Modifiable	Notes
activate_all_roles_on_login	Yes	This parameter applies to Aurora MySQL version 3.
allow-suspicious-udfs	No
aurora_disable_hash_join	Yes	Set this parameter to ON to turn off hash join optimization in Aurora MySQL version 2.09 or higher. It isn't supported for version 3. For more information, see Parallel query for Amazon Aurora MySQL.
aurora_lab_mode	Yes	For more information, see Amazon Aurora MySQL lab mode. Removed from Aurora MySQL version 3.
aurora_oom_response	Yes	This parameter is supported for Aurora MySQL versions 2 and 3. For more information, see Troubleshooting out-of-memory issues for Aurora MySQL databases.
aurora_parallel_query	Yes	Set to ON to turn on parallel query in Aurora MySQL version 2.09 or higher. The old aurora_pq parameter isn't used in these versions. For more information, see Parallel query for Amazon Aurora MySQL.
aurora_pq	Yes	Set to OFF to turn off parallel query for specific DB instances in Aurora MySQL versions before 2.09. In version 2.09 or higher, turn parallel query on and off with aurora_parallel_query instead. For more information, see Parallel query for Amazon Aurora MySQL.
aurora_read_replica_read_committed	Yes	Enables READ COMMITTED isolation level for Aurora Replicas and changes the isolation behavior to reduce purge lag during long-running queries. Enable this setting only if you understand the behavior changes and how they affect your query results. For example, this setting uses less-strict isolation than the MySQL default. When it's enabled, long-running queries might see more than one copy of the same row because Aurora reorganizes the table data while the query is running. For more information, see Aurora MySQL isolation levels.
aurora_tmptable_enable_per_table_limit	Yes	Determines whether the tmp_table_size parameter controls the maximum size of in-memory temporary tables created by the TempTable storage engine in Aurora MySQL version 3.04 and higher. For more information, see Limiting the size of internal, in-memory temporary tables.
aurora_use_vector_instructions	Yes	When this parameter is enabled, Aurora MySQL uses optimized vector processing instructions provided by modern CPUs to improve performance on I/O-intensive workloads. This setting is enabled by default in Aurora MySQL version 3.05 and higher.
autocommit	Yes
automatic_sp_privileges	Yes
back_log	Yes
basedir	No	Aurora MySQL uses managed instances where you don't access the file system directly.
binlog_cache_size	Yes
binlog_max_flush_queue_time	Yes
binlog_order_commits	Yes
binlog_stmt_cache_size	Yes
binlog_transaction_compression	Yes	This parameter applies to Aurora MySQL version 3.
binlog_transaction_compression_level_zstd	Yes	This parameter applies to Aurora MySQL version 3.
bulk_insert_buffer_size	Yes
concurrent_insert	Yes
connect_timeout	Yes
core-file	No	Aurora MySQL uses managed instances where you don't access the file system directly.
datadir	No	Aurora MySQL uses managed instances where you don't access the file system directly.
default_authentication_plugin	No	This parameter applies to Aurora MySQL version 3.
default_time_zone	No
default_tmp_storage_engine	Yes	The default storage engine for temporary tables.
default_week_format	Yes
delay_key_write	Yes
delayed_insert_limit	Yes
delayed_insert_timeout	Yes
delayed_queue_size	Yes
div_precision_increment	Yes
end_markers_in_json	Yes
eq_range_index_dive_limit	Yes
event_scheduler	Sometimes	Indicates the status of the Event Scheduler. Modifiable only at the cluster level in Aurora MySQL version 3.
explicit_defaults_for_timestamp	Yes
flush	No
flush_time	Yes
ft_boolean_syntax	No
ft_max_word_len	Yes
ft_min_word_len	Yes
ft_query_expansion_limit	Yes
ft_stopword_file	Yes
general_log	Yes	For instructions on uploading the logs to CloudWatch Logs, see Publishing Amazon Aurora MySQL logs to Amazon CloudWatch Logs.
general_log_file	No	Aurora MySQL uses managed instances where you don't access the file system directly.
group_concat_max_len	Yes
host_cache_size	Yes
init_connect	Yes	The command to be run by the server for each client that connects. Use double quotes (") for settings to avoid connection failures, for example: SET optimizer_switch="hash_join=off" In Aurora MySQL version 3, this parameter doesn't apply for users who have the CONNECTION_ADMIN privilege, including the Aurora master user. For more information, see Role-based privilege model.
innodb_adaptive_hash_index	Yes	You can modify this parameter at the DB instance level in Aurora MySQL version 2. It's modifiable only at the DB cluster level in Aurora MySQL version 3. The Adaptive Hash Index isn't supported on reader DB instances.
innodb_adaptive_max_sleep_delay	Yes	Modifying this parameter has no effect because innodb_thread_concurrency is always 0 for Aurora.
innodb_aurora_max_partitions_for_range	Yes	In some cases where persisted statistics aren't available, you can use this parameter to improve the performance of row count estimations on partitioned tables. You can set it to a value from 0–8192, where the value determines the number of partitions to check during row count estimation. The default value is 0, which estimates using all of the partitions, consistent with default MySQL behavior. This parameter is available for Aurora MySQL version 3.03.1 and higher.
innodb_autoextend_increment	Yes
innodb_buffer_pool_dump_at_shutdown	No
innodb_buffer_pool_dump_now	No
innodb_buffer_pool_filename	No
innodb_buffer_pool_load_abort	No
innodb_buffer_pool_load_at_startup	No
innodb_buffer_pool_load_now	No
innodb_buffer_pool_size	Yes	The default value is represented by a formula. For details about how the DBInstanceClassMemory value in the formula is calculated, see DB parameter formula variables.
innodb_change_buffer_max_size	No	Aurora MySQL doesn't use the InnoDB change buffer at all.
innodb_compression_failure_threshold_pct	Yes
innodb_compression_level	Yes
innodb_compression_pad_pct_max	Yes
innodb_concurrency_tickets	Yes	Modifying this parameter has no effect, because innodb_thread_concurrency is always 0 for Aurora.
innodb_deadlock_detect	Yes	This option is used to disable deadlock detection in Aurora MySQL version 2.11 and higher and version 3. On high-concurrency systems, deadlock detection can cause a slowdown when numerous threads wait for the same lock. Consult the MySQL documentation for more information on this parameter.
innodb_file_format	Yes	Removed from Aurora MySQL version 3.
innodb_flushing_avg_loops	No
innodb_force_load_corrupted	No
innodb_ft_aux_table	Yes
innodb_ft_cache_size	Yes
innodb_ft_enable_stopword	Yes
innodb_ft_server_stopword_table	Yes
innodb_ft_user_stopword_table	Yes
innodb_large_prefix	Yes	Removed from Aurora MySQL version 3.
innodb_lock_wait_timeout	Yes
innodb_log_compressed_pages	No
innodb_lru_scan_depth	Yes
innodb_max_purge_lag	Yes
innodb_max_purge_lag_delay	Yes
innodb_monitor_disable	Yes
innodb_monitor_enable	Yes
innodb_monitor_reset	Yes
innodb_monitor_reset_all	Yes
innodb_old_blocks_pct	Yes
innodb_old_blocks_time	Yes
innodb_open_files	Yes
innodb_print_all_deadlocks	Yes	When turned on, records information about all InnoDB deadlocks in the Aurora MySQL error log. For more information, see Minimizing and troubleshooting Aurora MySQL deadlocks.
innodb_random_read_ahead	Yes
innodb_read_ahead_threshold	Yes
innodb_read_io_threads	No
innodb_read_only	No	Aurora MySQL manages the read-only and read/write state of DB instances based on the type of cluster. For example, a provisioned cluster has one read/write DB instance (the primary instance) and any other instances in the cluster are read-only (the Aurora Replicas).
innodb_replication_delay	Yes
innodb_sort_buffer_size	Yes
innodb_stats_auto_recalc	Yes
innodb_stats_method	Yes
innodb_stats_on_metadata	Yes
innodb_stats_persistent	Yes
innodb_stats_persistent_sample_pages	Yes
innodb_stats_transient_sample_pages	Yes
innodb_thread_concurrency	No
innodb_thread_sleep_delay	Yes	Modifying this parameter has no effect because innodb_thread_concurrency is always 0 for Aurora.
interactive_timeout	Yes	Aurora evaluates the minimum value of interactive_timeout and wait_timeout. It then uses that minimum as the timeout to end all idle sessions, both interactive and noninteractive.
internal_tmp_disk_storage_engine	Yes	Controls which in-memory storage engine is used for internal temporary tables. Allowed values are INNODB and MYISAM. This parameter applies to Aurora MySQL version 2.
internal_tmp_mem_storage_engine	Sometimes	Controls which in-memory storage engine is used for internal temporary tables. Allowed values for writer DB instances are MEMORY and TempTable. For reader DB instances, this parameter is set to TempTable and can't be modified. This parameter applies to Aurora MySQL version 3.
join_buffer_size	Yes
keep_files_on_create	Yes
key_buffer_size	Yes	Key cache for MyISAM tables. For more information, see keycache->cache_lock mutex.
key_cache_age_threshold	Yes
key_cache_block_size	Yes
key_cache_division_limit	Yes
local_infile	Yes
lock_wait_timeout	Yes
log-bin	No	Setting binlog_format to STATEMENT, MIXED, or ROW automatically sets log-bin to ON. Setting binlog_format to OFF automatically sets log-bin to OFF. For more information, see Replication between Aurora and MySQL or between Aurora and another Aurora DB cluster (binary log replication).
log_bin_trust_function_creators	Yes
log_bin_use_v1_row_events	Yes	Removed from Aurora MySQL version 3.
log_error	No
log_error_suppression_list	Yes	Specifies a list of error codes that aren't logged in the MySQL error log. This allows you to ignore certain noncritical error conditions to help keep your error logs clean. For more information, see log_error_suppression_list in the MySQL documentation. This parameter applies to Aurora MySQL version 3.03 and higher.
log_output	Yes
log_queries_not_using_indexes	Yes
log_slave_updates	No	Aurora MySQL version 2. Use log_replica_updates in Aurora MySQL version 3.
log_replica_updates	No	Aurora MySQL version 3
log_throttle_queries_not_using_indexes	Yes
log_warnings	Yes	Removed from Aurora MySQL version 3.
long_query_time	Yes
low_priority_updates	Yes	INSERT, UPDATE, DELETE, and LOCK TABLE WRITE operations wait until there's no pending SELECT operation. This parameter affects only storage engines that use only table-level locking (MyISAM, MEMORY, MERGE). This parameter applies to Aurora MySQL version 3.
max_allowed_packet	Yes
max_binlog_cache_size	Yes
max_binlog_size	No
max_binlog_stmt_cache_size	Yes
max_connect_errors	Yes
max_connections	Yes	The default value is represented by a formula. For details about how the DBInstanceClassMemory value in the formula is calculated, see DB parameter formula variables. For the default values depending on the instance class, see Maximum connections to an Aurora MySQL DB instance.
max_delayed_threads	Yes	Sets the maximum number of threads to handle INSERT DELAYED statements. This parameter applies to Aurora MySQL version 3.
max_error_count	Yes	The maximum number of error, warning, and note messages to be stored for display. This parameter applies to Aurora MySQL version 3.
max_execution_time	Yes	The timeout for running SELECT statements, in milliseconds. The value can be from 0–18446744073709551615. When set to 0, there is no timeout. For more information, see max_execution_time in the MySQL documentation.
max_heap_table_size	Yes
max_insert_delayed_threads	Yes
max_join_size	Yes
max_length_for_sort_data	Yes	Removed from Aurora MySQL version 3.
max_prepared_stmt_count	Yes
max_seeks_for_key	Yes
max_sort_length	Yes
max_sp_recursion_depth	Yes
max_tmp_tables	Yes	Removed from Aurora MySQL version 3.
max_user_connections	Yes
max_write_lock_count	Yes
metadata_locks_cache_size	Yes	Removed from Aurora MySQL version 3.
min_examined_row_limit	Yes	Use this parameter to prevent queries that examine fewer than the specified number of rows from being logged. This parameter applies to Aurora MySQL version 3.
myisam_data_pointer_size	Yes
myisam_max_sort_file_size	Yes
myisam_mmap_size	Yes
myisam_sort_buffer_size	Yes
myisam_stats_method	Yes
myisam_use_mmap	Yes
net_buffer_length	Yes
net_read_timeout	Yes
net_retry_count	Yes
net_write_timeout	Yes
old-style-user-limits	Yes
old_passwords	Yes	Removed from Aurora MySQL version 3.
optimizer_prune_level	Yes
optimizer_search_depth	Yes
optimizer_switch	Yes	For information about Aurora MySQL features that use this switch, see Best practices with Amazon Aurora MySQL.
optimizer_trace	Yes
optimizer_trace_features	Yes
optimizer_trace_limit	Yes
optimizer_trace_max_mem_size	Yes
optimizer_trace_offset	Yes
performance-schema-consumer-events-waits-current	Yes
performance-schema-instrument	Yes
performance_schema	Yes
performance_schema_accounts_size	Yes
performance_schema_consumer_global_instrumentation	Yes
performance_schema_consumer_thread_instrumentation	Yes
performance_schema_consumer_events_stages_current	Yes
performance_schema_consumer_events_stages_history	Yes
performance_schema_consumer_events_stages_history_long	Yes
performance_schema_consumer_events_statements_current	Yes
performance_schema_consumer_events_statements_history	Yes
performance_schema_consumer_events_statements_history_long	Yes
performance_schema_consumer_events_waits_history	Yes
performance_schema_consumer_events_waits_history_long	Yes
performance_schema_consumer_statements_digest	Yes
performance_schema_digests_size	Yes
performance_schema_events_stages_history_long_size	Yes
performance_schema_events_stages_history_size	Yes
performance_schema_events_statements_history_long_size	Yes
performance_schema_events_statements_history_size	Yes
performance_schema_events_transactions_history_long_size	Yes
performance_schema_events_transactions_history_size	Yes
performance_schema_events_waits_history_long_size	Yes
performance_schema_events_waits_history_size	Yes
performance_schema_hosts_size	Yes
performance_schema_max_cond_classes	Yes
performance_schema_max_cond_instances	Yes
performance_schema_max_digest_length	Yes
performance_schema_max_file_classes	Yes
performance_schema_max_file_handles	Yes
performance_schema_max_file_instances	Yes
performance_schema_max_index_stat	Yes
performance_schema_max_memory_classes	Yes
performance_schema_max_metadata_locks	Yes
performance_schema_max_mutex_classes	Yes
performance_schema_max_mutex_instances	Yes
performance_schema_max_prepared_statements_instances	Yes
performance_schema_max_program_instances	Yes
performance_schema_max_rwlock_classes	Yes
performance_schema_max_rwlock_instances	Yes
performance_schema_max_socket_classes	Yes
performance_schema_max_socket_instances	Yes
performance_schema_max_sql_text_length	Yes
performance_schema_max_stage_classes	Yes
performance_schema_max_statement_classes	Yes
performance_schema_max_statement_stack	Yes
performance_schema_max_table_handles	Yes
performance_schema_max_table_instances	Yes
performance_schema_max_table_lock_stat	Yes
performance_schema_max_thread_classes	Yes
performance_schema_max_thread_instances	Yes
performance_schema_session_connect_attrs_size	Yes
performance_schema_setup_actors_size	Yes
performance_schema_setup_objects_size	Yes
performance_schema_show_processlist	Yes	This parameter determines which SHOW PROCESSLIST implementation to use: The default implementation iterates across active threads from within the thread manager while holding a global mutex. This can cause slow performance, especially on busy systems. The alternative SHOW PROCESSLIST implementation is based on the Performance Schema processlist table. This implementation queries active thread data from the Performance Schema rather than the thread manager and doesn't require a mutex. This parameter applies to Aurora MySQL version 2.12 and higher, and version 3.
performance_schema_users_size	Yes
pid_file	No
plugin_dir	No	Aurora MySQL uses managed instances where you don't access the file system directly.
port	No	Aurora MySQL manages the connection properties and enforces consistent settings for all DB instances in a cluster.
preload_buffer_size	Yes	The size of the buffer that's allocated when preloading indexes. This parameter applies to Aurora MySQL version 3.
profiling_history_size	Yes
query_alloc_block_size	Yes
query_cache_limit	Yes	Removed from Aurora MySQL version 3.
query_cache_min_res_unit	Yes	Removed from Aurora MySQL version 3.
query_cache_size	Yes	The default value is represented by a formula. For details about how the DBInstanceClassMemory value in the formula is calculated, see DB parameter formula variables. Removed from Aurora MySQL version 3.
query_cache_type	Yes	Removed from Aurora MySQL version 3.
query_cache_wlock_invalidate	Yes	Removed from Aurora MySQL version 3.
query_prealloc_size	Yes
range_alloc_block_size	Yes
read_buffer_size	Yes
read_only	Yes	When this parameter is turned on, the server permits no updates except from those performed by replica threads. For Aurora MySQL version 2, valid values are the following: 0 – OFF 1 – ON {TrueIfReplica} – ON for read replicas. This is the default value. {TrueIfClusterReplica} – ON for instances in replica clusters such as cross-Region read replicas, secondary clusters in an Aurora global database, and blue/green deployments. We recommend that you use the DB cluster parameter group in Aurora MySQL version 2 to make sure that the read_only parameter is applied to new writer instances on failover. Note Reader instances are always read only, because Aurora MySQL sets innodb_read_only to 1 on all readers. Therefore, read_only is redundant on reader instances. Removed at the instance level from Aurora MySQL version 3.
read_rnd_buffer_size	Yes
relay-log	No
relay_log_info_repository	Yes	Removed from Aurora MySQL version 3.
relay_log_recovery	No
replica_checkpoint_group	Yes	Aurora MySQL version 3
replica_checkpoint_period	Yes	Aurora MySQL version 3
replica_parallel_workers	Yes	Aurora MySQL version 3
replica_pending_jobs_size_max	Yes	Aurora MySQL version 3
replica_skip_errors	Yes	Aurora MySQL version 3
replica_sql_verify_checksum	Yes	Aurora MySQL version 3
safe-user-create	Yes
secure_auth	Yes	This parameter is always turned on in Aurora MySQL version 2. Trying to turn it off generates an error. Removed from Aurora MySQL version 3.
secure_file_priv	No	Aurora MySQL uses managed instances where you don't access the file system directly.
show_create_table_verbosity	Yes	Enabling this variable causes SHOW_CREATE_TABLE to display the ROW_FORMAT regardless of whether it's the default format. This parameter applies to Aurora MySQL version 2.12 and higher, and version 3.
skip-slave-start	No
skip_external_locking	No
skip_show_database	Yes
slave_checkpoint_group	Yes	Aurora MySQL version 2. Use replica_checkpoint_group in Aurora MySQL version 3.
slave_checkpoint_period	Yes	Aurora MySQL version 2. Use replica_checkpoint_period in Aurora MySQL version 3.
slave_parallel_workers	Yes	Aurora MySQL version 2. Use replica_parallel_workers in Aurora MySQL version 3.
slave_pending_jobs_size_max	Yes	Aurora MySQL version 2. Use replica_pending_jobs_size_max in Aurora MySQL version 3.
slave_sql_verify_checksum	Yes	Aurora MySQL version 2. Use replica_sql_verify_checksum in Aurora MySQL version 3.
slow_launch_time	Yes
slow_query_log	Yes	For instructions on uploading the logs to CloudWatch Logs, see Publishing Amazon Aurora MySQL logs to Amazon CloudWatch Logs.
slow_query_log_file	No	Aurora MySQL uses managed instances where you don't access the file system directly.
socket	No
sort_buffer_size	Yes
sql_mode	Yes
sql_select_limit	Yes
stored_program_cache	Yes
sync_binlog	No
sync_master_info	Yes
sync_source_info	Yes	This parameter applies to Aurora MySQL version 3.
sync_relay_log	Yes	Removed from Aurora MySQL version 3.
sync_relay_log_info	Yes
sysdate-is-now	Yes
table_cache_element_entry_ttl	No
table_definition_cache	Yes	The default value is represented by a formula. For details about how the DBInstanceClassMemory value in the formula is calculated, see DB parameter formula variables.
table_open_cache	Yes	The default value is represented by a formula. For details about how the DBInstanceClassMemory value in the formula is calculated, see DB parameter formula variables.
table_open_cache_instances	Yes
temp-pool	Yes	Removed from Aurora MySQL version 3.
temptable_max_mmap	Yes	This parameter applies to Aurora MySQL version 3. For details, see New temporary table behavior in Aurora MySQL version 3.
temptable_max_ram	Yes	This parameter applies to Aurora MySQL version 3. For details, see New temporary table behavior in Aurora MySQL version 3.
temptable_use_mmap	Yes	This parameter applies to Aurora MySQL version 3. For details, see New temporary table behavior in Aurora MySQL version 3.
thread_cache_size	Yes	The number of threads to be cached. This parameter applies to Aurora MySQL versions 2 and 3.
thread_handling	No
thread_stack	Yes
timed_mutexes	Yes
tmp_table_size	Yes	Defines the maximum size of internal in-memory temporary tables created by the MEMORY storage engine in Aurora MySQL version 3. In Aurora MySQL version 3.04 and higher, defines the maximum size of internal in-memory temporary tables created by the TempTable storage engine when aurora_tmptable_enable_per_table_limit is ON. For more information, see Limiting the size of internal, in-memory temporary tables.
tmpdir	No	Aurora MySQL uses managed instances where you don't access the file system directly.
transaction_alloc_block_size	Yes
transaction_isolation	Yes	This parameter applies to Aurora MySQL version 3. It replaces tx_isolation.
transaction_prealloc_size	Yes
tx_isolation	Yes	Removed from Aurora MySQL version 3. It is replaced by transaction_isolation.
updatable_views_with_limit	Yes
validate-password	No
validate_password_dictionary_file	No
validate_password_length	No
validate_password_mixed_case_count	No
validate_password_number_count	No
validate_password_policy	No
validate_password_special_char_count	No
wait_timeout	Yes	Aurora evaluates the minimum value of interactive_timeout and wait_timeout. It then uses that minimum as the timeout to end all idle sessions, both interactive and noninteractive.

MySQL parameters that don't apply to Aurora MySQL

Because of architectural differences between Aurora MySQL and MySQL, some MySQL parameters don't apply to Aurora MySQL.

The following MySQL parameters don't apply to Aurora MySQL. This list isn't exhaustive.

• activate_all_roles_on_login – This parameter doesn't apply to Aurora MySQL version 2. It is available in Aurora MySQL version 3.

• big_tables

• bind_address

• character_sets_dir

• innodb_adaptive_flushing

• innodb_adaptive_flushing_lwm

• innodb_buffer_pool_chunk_size

• innodb_buffer_pool_instances

• innodb_change_buffering

• innodb_checksum_algorithm

• innodb_data_file_path

• innodb_dedicated_server

• innodb_doublewrite

• innodb_flush_log_at_timeout – This parameter doesn't apply to Aurora MySQL. For more information, see Configuring how frequently the log buffer is flushed.

• innodb_flush_method

• innodb_flush_neighbors

• innodb_io_capacity

• innodb_io_capacity_max

• innodb_log_buffer_size

• innodb_log_file_size

• innodb_log_files_in_group

• innodb_log_spin_cpu_abs_lwm

• innodb_log_spin_cpu_pct_hwm

• innodb_log_writer_threads

• innodb_max_dirty_pages_pct

• innodb_numa_interleave

• innodb_page_size

• innodb_redo_log_capacity

• innodb_redo_log_encrypt

• innodb_undo_log_encrypt

• innodb_undo_log_truncate

• innodb_undo_logs

• innodb_undo_tablespaces

• innodb_use_native_aio

• innodb_write_io_threads