Parameter overview|V4.2.1|OceanBase Database| docs|Distributed Database

Parameter name	Feature description
mysql_port	Sets the port number for the SQL service protocol.
rpc_port	Sets the protocol port number for remote access.
sql_protocol_min_tls_version	Sets the minimum version of the SSL/TLS protocol to be used for SSL connections in SQL statements.
ssl_client_authentication	Specifies whether to enable the SSL connection feature.
ssl_client_authentication	Specifies whether to enable the SSL connection feature.
ssl_external_kms_info	Used to record information required for the SSL feature of OceanBase Database to function. It records the configuration dependencies for different SSL usage methods in a JSON string format. The JSON must contain at least the type.`ssl_mode`field.
enable_sql_audit	Specifies whether to enable the SQL audit feature.

Parameter name	Feature description
backup_backup_dest	Specifies the backup destination for the backup data.
backup_backup_dest_option	Parameters for controlling backup operations.
backup_dest_option	Parameters related to backup.
backup_concurrency	Specifies the number of concurrent threads that write data to the file system during backup.
backup_dest	The path for setting the baseline backup and log archive.
backup_log_archive_option	Defines the archiving options for backup logs.
backup_net_limit	Sets the total bandwidth for cluster backup.
backup_recovery_window	Specifies the point in time to which backup data can be restored.
backup_region	Specifies the region for backup execution.
backup_zone	Specifies the zone for backup execution.
log_archive_batch_buffer_limit	This parameter specifies the maximum memory usage of a single node for log archiving.
log_archive_checkpoint_interval	Sets the time interval for log archiving checkpoints of cold data.
restore_concurrency	Sets the maximum concurrency for restoring tenant data from a backup.

Parameter name	Feature description
enable_cgroup	This parameter specifies whether to enable the Cgroup feature for the OBServer node.

Parameter name	Feature description
cpu_count	Sets the total number of system CPUs. If set to 0, the system automatically detects the number of CPUs.
server_balance_cpu_mem_tolerance_percent	In the node load balancing strategy, this parameter is used to set the tolerance for CPU and memory resource imbalance.
server_cpu_quota_max	Sets the maximum CPU quota that the system can use.
server_cpu_quota_min	Sets the minimum CPU quota available for the system, which is automatically reserved.
token_reserved_percentage	In tenant CPU scheduling, it specifies the proportion of idle tokens reserved for the tenant each time.
workers_per_cpu_quota	Sets the number of worker threads allocated to each CPU.
cpu_reserved	This parameter specifies the number of CPU cores reserved for the system. The remaining CPU cores will be exclusively used by OceanBase Database.
sys_cpu_limit_trigger	This parameter specifies the CPU utilization threshold. When the CPU utilization exceeds this threshold, system background tasks will be suspended.
system_cpu_quota	Sets the CPU quota available to the sys tenant.
tenant_cpu_variation_per_server	It is used to set the allowed deviation for CPU quota scheduling among multiple units of a tenant.

Parameter name	Feature description
enable_dblink	Controls whether to enable the DBLink feature.

Parameter name	Feature description
weak_read_version_refresh_interval	Sets the refresh interval for the weak-consistency read version number, which affects the latency of weak-consistency reads.
large_query_worker_percentage	Sets the percentage of worker threads reserved for processing large queries.
large_query_threshold	Sets the threshold for query execution time.
trace_log_slow_query_watermark	Sets the execution time threshold for queries. If a query's execution time exceeds this threshold, it is considered a slow query, and its trace logs are printed to the system logs.

Parameter name	Feature description
balancer_task_timeout	Sets the timeout period for background tasks such as load balancing.
balancer_tolerance_percentage	This parameter specifies the tolerance for disk imbalance among multiple units within a tenant under the load balancing strategy. If the disk usage deviates from the average by less than or equal to this tolerance, no balancing action is triggered.
server_balance_critical_disk_waterlevel	Used to set the watermarks for the load balancing feature of disk space.
server_balance_disk_tolerance_percent	This parameter specifies the tolerance for imbalance in the disk load balancing strategy among nodes.
resource_hard_limit	Specifies the CPU overprovisioning percentage.
enable_sys_unit_standalone	Sets whether the unit of the system tenant is exclusive to a node.
balancer_emergency_percentage	Sets the UNIT load threshold. When the UNIT load exceeds this threshold, replica migration out is allowed, and load balancing is performed even during major compactions.
balancer_timeout_check_interval	It is used to set the timeout interval for checking backend tasks such as load balancing.
data_copy_concurrency	This parameter specifies the maximum number of data migration replication tasks that can be executed concurrently in the system.
tenant_groups	Specifies the tenant group used in the load balancing strategy.
unit_balance_resource_weight	It is used to set the resource weight used in the UNIT balancing strategy and generally does not require manual configuration.
resource_soft_limit	Specifies whether to enable unit balancing.

Parameter name	Feature description
enable_rereplication	The master switch for automatic migration and replication of log stream replicas.
ls_meta_table_check_interval	This parameter is used to set the check interval for the background inspection thread of the DBA_OB_LS_LOCATIONS/CDB_OB_LS_LOCATIONS view.
sys_bkgd_migration_change_member_list_timeout	Sets the timeout period for changing the Paxos member group during replica migration.
sys_bkgd_migration_retry_num	Specifies the maximum number of retries allowed when a replica migration fails.
balance_blacklist_failure_threshold	The number of consecutive failures for background tasks such as replica migration. When the number of consecutive failures exceeds this threshold, the task will be placed in the blacklist.
balance_blacklist_retry_interval	Specifies the retry interval for background tasks, such as replica migration, after they are placed in the blacklist.
election_cpu_quota	It is used to set the CPU quota allocated for background tasks related to replica election.
election_blacklist_interval	Specifies the time interval during which a primary replica cannot be re-elected as the primary after it is abandoned.
enable_auto_leader_switch	Specifies whether to enable automatic leader switchover.
enable_smooth_leader_switch	It is the switch for the smooth leader switchover feature.
global_index_build_single_replica_timeout	Specifies the timeout period for each replica during global index creation.
get_leader_candidate_rpc_timeout	Sets the internal request timeout period for obtaining candidates in the automatic leader switchover policy.
migrate_concurrency	Sets the maximum concurrency for internal data migration.
rebuild_replica_data_lag_threshold	The threshold for the transaction log lag between the standby replica and the primary replica. When this threshold is exceeded, replica reconstruction is triggered.
server_data_copy_out_concurrency	Specifies the maximum number of concurrent data migrations from a single node.
server_data_copy_in_concurrency	Specifies the maximum number of concurrent data migrations to a single node.
replica_safe_remove_time	Specifies the maximum period for which deleted replicas can be retained before they are cleaned up.

Parameter name	Feature description
bf_cache_miss_count_threshold	Controls the number of times a Bloomfilter cache is triggered. A Bloomfilter cache is created when the number of misses in a macroblock reaches this value.
bf_cache_priority	Sets the Bloom filter cache priority.
cache_wash_threshold	The capacity threshold for triggering cache cleanup.
fuse_row_cache_priority	Sets the priority of the fused row cache in the caching system.
user_row_cache_priority	Sets the priority of baseline data row cache in the caching system.
autoinc_cache_refresh_interval	Sets the refresh interval for the auto-increment column cache.
plan_cache_evict_interval	Sets the eviction interval for the plan cache.
index_block_cache_priority	Sets the cache priority for metadata index microblocks.
opt_tab_stat_cache_priority	Sets the cache priority for statistics.
tablet_ls_cache_priority	Sets the priority of tablet mapping cache.
user_block_cache_priority	This parameter specifies the priority of data block cache in the cache system.
index_info_block_cache_priority	Sets the priority of a block index in the caching system.
index_cache_priority	Used to set the index's priority in the caching system.
user_tab_col_stat_cache_priority	Sets the priority for caching statistics in the cache system.
plan_cache_high_watermark	Sets the memory usage threshold for the plan cache. When the cache usage exceeds this threshold, automatic eviction is triggered.
plan_cache_low_watermark	The threshold for the memory occupied by the plan cache. Evictions will stop when the memory usage drops below this threshold.

Parameter name	Feature description
tablet_meta_table_check_interval	This parameter specifies the check interval for the background inspection thread of the DBA_OB_TABLET_REPLICAS or CDB_OB_TABLET_REPLICAS view.
tablet_meta_table_scan_batch_count	Specifies the number of tablets cached in memory during the iteration of a tablet meta table.
tablet_size	It specifies the size of each shard during internal parallel processing (such as major compactions and queries) within a partition.
auto_broadcast_location_cache_rate_limit	Sets the maximum number of partitions whose location changes that each OBServer can broadcast per second.
auto_refresh_location_cache_rate_limit	Specifies the maximum number of partitions that each OBServer node can trigger auto-refresh for per second.
enable_pg	Specifies whether to enable the partition group feature.
gc_wait_archive	Specifies whether to wait for all logs on a partition to be archived before initiating garbage collection (GC) for the partition.
partition_table_check_interval	Sets the time interval for an OBServer node to delete non-existent replicas from a partitioned table.

Parameter name	Feature description
sql_net_thread_count	It specifies the number of I/O threads in a MySQL cluster.`global_sql_nio_server`The number of threads. The default value of 0 indicates that the number of threads is determined by the parameter`net_thread_count`have the same value.
auto_leader_switch_interval	Sets the working interval for the background thread that performs automatic leader switchover.
switchover_process_thread_count	Sets the size of the thread pool related to primary/standby switchover.

Parameter name	Feature description
rdma_io_thread_count	Specifies the number of RDMA I/O threads for Libreasy.
syslog_io_bandwidth_limit	This parameter specifies the maximum disk I/O bandwidth that system logs can consume. System logs exceeding this bandwidth limit will be discarded.
disk_io_thread_count	The number of threads for disk I/O. It must be an even number.
net_thread_count	Sets the number of network I/O threads.
data_storage_error_tolerance_time	Used to control the data disk status to`ERROR`The tolerance time for the status.
sys_bkgd_io_high_percentage	Sets the maximum percentage of system background I/O usage.
sys_bkgd_io_low_percentage	The minimum percentage of system background I/O usage.
user_iort_up_percentage	This parameter specifies the threshold for user disk I/O latency. When the user disk I/O latency exceeds this threshold, the system will throttle background I/O tasks.
ob_esi_rpc_port	Sets the communication port between the OBESE process and the OBSERVER process.
enable_ob_esi_process	Used to control whether to enable the obesi (external storage interface) process.
ob_esi_session_timeout	Sets the timeout period for an obese process holding active session resources.
ob_esi_io_concurrency	Sets the number of concurrent I/O operations for the OBDI process.
ob_esi_syslog_level	Sets the current logging level for the OBESE process.
ob_esi_max_syslog_file_count	Specifies the maximum number of log files that the OBDI process can accommodate before recycling log files.
multiblock_read_gap_size	Sets the maximum size of the block cache for a single I/O aggregate read.
multiblock_read_size	This parameter specifies the I/O aggregation size for data reading.

Parameter name	Feature description
all_server_list	Displays the addresses of all servers in the cluster.
cluster	Sets the name of the current OceanBase cluster.
cluster_id	Sets the ID of the current OceanBase cluster.
rpc_timeout	Sets the timeout period for internal requests within the cluster.
all_cluster_list	Displays the list of servers accessing the same config_url.
enable_election_group	Specifies whether to enable the election group strategy.
local_ip	The IP address of the server where the OBServer node is to be installed.
observer_id	The unique identifier for assigning RS to an OBServer node in a cluster.
min_observer_version	This API is used to view the minimum application version number of OBServer nodes in the cluster.

Parameter name	Feature description
enable_ob_ratelimit	This API is used to enable inter-region rate limiting in an RPC connection.
ob_ratelimit_stat_period	Sets the time interval for calculating and updating the maximum bandwidth on an OBServer node.

Parameter name	Feature description
virtual_table_location_cache_expire_time	Sets the cache expiration time for the virtual table location information.
location_cache_refresh_rpc_timeout	Refresh via RPC`location_cache`The timeout period.
location_cache_refresh_sql_timeout	Refresh via SQL`location_cache`The timeout period.
location_cache_refresh_min_interval	Sets the minimum interval for refreshing location cache requests to prevent excessive refresh requests from overwhelming the system.
location_cache_cpu_quota	Sets the CPU quota for the location caching module.
location_fetch_concurrency	Sets the maximum concurrency for refreshing the local cache on a single node.
location_refresh_thread_count	Specifies the number of threads used by an OBServer node to obtain partition location information from the root service.
enable_auto_refresh_location_cache	This parameter specifies whether to enable automatic refresh of the location cache.

Parameter name	Feature description
config_additional_dir	Specifies multiple directories for storing the configuration file locally to achieve redundant storage of multiple configuration files.
data_dir	The directory for storing data such as SSTables.

Parameter name	Feature description
datafile_disk_percentage	It indicates the percentage of the total space of the disk where data_dir is located that is occupied by OceanBase Database. The disk where data_dir is located will be initialized by the OceanBase Database system for data storage.
data_disk_usage_limit_percentage	It specifies the maximum percentage of data files that can be written. When this threshold is exceeded, data migration in is prohibited.
enable_sql_operator_dump	It specifies whether to allow intermediate results of SQL processing to be written to disk to free up memory.
global_write_halt_residual_memory	Used to set the threshold for triggering a pause on write operations for regular tenants.`sys`The global remaining memory threshold (which does not affect tenants).
leak_mod_to_check	This is used for memory leak detection and is an internal debugging feature.
memory_chunk_cache_size	The capacity of memory blocks cached by the memory allocator.
memory_limit	Indicates the total available memory size.
memory_limit_percentage	It specifies the percentage of the total memory size that is available for the system.
memory_reserved	Sets the memory capacity reserved by the system for KVCache.
memstore_limit_percentage	Sets the percentage of a tenant's total available memory that can be used by the MemStore.
system_memory	Used to set the system-reserved ID for the tenant.`500`The memory capacity of the tenant.
use_large_pages	Manages large memory pages used by the database.
datafile_maxsize	Specifies the maximum size for automatic disk file expansion.
datafile_next	Specifies the growth step for automatic disk file expansion.
storage_meta_cache_priority	Used to control the priority of storing Meta Cache in KVCache.

Parameter name	Feature description
px_workers_per_cpu_quota	Sets the ratio of worker threads for parallel execution.
px_task_size	It specifies the amount of data processed by each task in the SQL parallel query engine.
max_px_worker_count	Sets the maximum number of threads for the SQL parallel query engine.

Parameter name	Feature description
builtin_db_data_verify_cycle	Specifies the data bad block self-check cycle, in days. A value of 0 indicates no check.
data_storage_warning_tolerance_time	Specifies the tolerance period for setting the data disk status to WARNING.
dead_socket_detection_timeout	The time interval for detecting invalid sockets.
migration_disable_time	This parameter specifies the duration for which data migration is paused when a node fails to migrate data in due to reasons such as full disk.
schema_history_expire_time	This parameter specifies the expiration time for historical metadata data.
datafile_size	Specifies the size of the data file. This parameter is generally not required.
devname	Specifies the name of the network interface card device bound to the service process.
enable_perf_event	This parameter specifies whether to enable the performance event collection feature.
enable_record_trace_id	Specifies whether to record the trace ID set on the application side.
enable_upgrade_mode	Specifies whether to enable upgrade mode. In upgrade mode, some system background functions are suspended.
enable_ddl	Specifies whether to allow DDL statements to be executed.
high_priority_net_thread_count	Sets the number of high-priority network threads. The value is`0`indicates that this feature is disabled.
obconfig_url	The URL address of the OBConfig service.
rpc_port	Sets the protocol port number for remote access.
stack_size	Sets the size of the program function call stack.
tenant_task_queue_size	Sets the request queue size for each tenant.
zone	The name of the zone where the node is located. This parameter generally does not need to be configured.
recyclebin_object_expire_time	Automatically purges expired schema objects from the recycle bin.
default_row_format	This parameter specifies the default row format to use when creating tables in MySQL-compatible mode.
sys_bkgd_net_percentage	It specifies the percentage of network bandwidth that background system tasks can occupy.
schema_history_recycle_interval	Used to set the internal execution of the system.`schema`The time interval for reclaiming records across multiple versions.
enable_asan_for_memory_context	When using ob_asan, this parameter specifies whether to allow ObAsanAllocator (the default is to use ObAllocator as the MemoryContext allocator).
ofs_list	The OFS (OceanBase File System, a distributed storage system independently designed by OceanBase Database) connection URL is saved for each zone. It is mainly used to meet the requirement of RootService to access files across zones in OFS deployment mode.

Parameter name	Feature description
rootservice_async_task_queue_size	Sets the size of the internal asynchronous task queue for RootService.
rootservice_async_task_thread_count	Sets the thread pool size for asynchronous tasks within the root service.
rootservice_list	Displays the list of servers where the root service and its replicas are located.
rootservice_ready_check_interval	Specifies the interval at which the root service waits and checks the cluster status after startup.
rootservice_memory_limit	Sets the maximum memory capacity limit for the Root Service.
lease_time	Sets the duration of the heartbeat lease.
server_check_interval	Sets the time interval for consistency check of server tables.
server_permanent_offline_time	This parameter specifies the time threshold for detecting a node heartbeat interruption. That is, after a node's heartbeat is interrupted for this duration, it is considered permanently offline, and its data replicas need to be automatically replenished.
ob_event_history_recycle_interval	Controls the recycling interval for historical events.
enable_rootservice_standalone	It specifies whether to allow the sys tenant and RootService to exclusively occupy the OBServer node.
fast_recovery_concurrency	Controls the concurrency for quick recovery tasks scheduled by RootService when executed on OBServer nodes.
wait_leader_batch_count	Specifies the maximum number of partitions that RootService can send for leader switchover at a time.

Parameter name	Feature description
rpc_client_authentication_method	Specifies the security authentication method for the RPC client.
rpc_server_authentication_method	This parameter specifies the security authentication method for the RPC server.

Parameter name	Feature description
sql_login_thread_count	Sets the number of threads for processing SQL login requests.
sql_audit_memory_limit	Sets the maximum memory that SQL audit data can occupy.
enable_sys_table_ddl	Specifies whether to allow manual creation of system tables.
internal_sql_execute_timeout	This parameter specifies the time interval for internal DML requests in the system.

Parameter name	Feature description
log_disk_size	Specifies the disk size for redo logs.
log_disk_percentage	Specifies the percentage of total disk space occupied by redo logs.
dtl_buffer_size	Sets the cache size used by the SQL data transfer module.
ignore_replay_checksum_error	Specifies whether to ignore checksum errors that occur during the replay of transaction logs.
trx_2pc_retry_interval	Specifies the time interval for automatic retries when a two-phase commit fails.
standby_fetch_log_bandwidth_limit	This parameter specifies the maximum total bandwidth that can be occupied per second for all servers in the cluster where the standby tenant resides to synchronize logs from the primary tenant.
log_storage_warning_tolerance_time	Specifies the time before the disk is marked as bad after failed I/O operations from the log disk trigger a leader switchover.
clog_disk_utilization_threshold	The threshold for controlling the reuse of clog or iLog disk space.
clog_expire_days	This parameter specifies the expiration time for clog files. A clog file is deleted when the time elapsed since its last modification exceeds the specified expiration time.
clog_cache_priority	Sets the priority of transaction log cache usage.
clog_disk_usage_limit_percentage	Specifies the maximum percentage of disk space available for transaction logs.
clog_sync_time_warn_threshold	This parameter specifies the alert threshold for transaction log synchronization duration. A WARN log is generated when the synchronization duration exceeds this value.
clog_transport_compress_func	Specifies the compression algorithm used for internal transaction log transmission.
enable_one_phase_commit	This parameter specifies whether to enable the one-phase commit optimization for transaction commits.
enable_separate_sys_clog	Specifies whether to store system transaction logs separately from user transaction logs.
flush_log_at_trx_commit	It is used to set the transaction log writing strategy when a transaction is committed.
ignore_replay_checksum_error	Specifies whether to ignore checksum errors that occur during the replay of transaction logs.
index_clog_cache_priority	Sets the priority of the transaction log index in the caching system.
ilog_index_expire_time	Sets the maximum time within which an OBServer node can read ILog files.
trx_force_kill_threshold	Specifies the maximum wait time for killing transactions when necessary due to freezing or leader switchover.

Parameter name	Feature description
trx_try_wait_lock_timeout	Sets the wait duration for row locks during statement execution.

Parameter name	Feature description
debug_sync_timeout	This API is used to enable the Debug Sync debugging switch and set its timeout period.
enable_rich_error_msg	This parameter specifies whether to add server address, time, trace ID and other debugging information to client messages.

Parameter name	Feature description
enable_tcp_keepalive	Used to enable or disable the keep-alive mechanism for client connections.
tcp_keepidle	Specifies the interval, in seconds, after which a Keepalive packet is sent if no data is transmitted over the client connection to the server.
tcp_keepintvl	Specifies the time interval, in seconds, between two consecutive heartbeat probes after the client connection heartbeat mechanism is enabled.
tcp_keepcnt	Specifies the maximum number of retries before closing an inactive connection.

Parameter name	Feature description
enable_record_trace_log	Specifies whether to record trace logs.
enable_async_syslog	Specifies whether to enable asynchronous system log writing.
enable_syslog_recycle	This parameter specifies whether to enable the feature of retaining old logs generated before an OBServer node is started.`max_syslog_file_count`Used together, they determine whether the recycling logic will consider old log files.
enable_syslog_wf	Specifies whether to log system logs of WARN level or above to a separate log file.
max_string_print_length	Specifies the maximum length of a single line of system log that can be printed.
max_syslog_file_count	Specifies the maximum number of log files that can be retained before recycled.
syslog_level	Sets the system log level.
trace_log_sampling_interval	Specifies the time for periodically printing trace log information.
diag_syslog_per_error_limit	Specifies the number of DIAG system logs allowed per second for each error code. Logs will no longer be printed once this threshold is exceeded.
enable_log_archive	Specifies whether to enable the log archiving feature.
system_trace_level	Sets the log level for system tracing logs.

Parameter name	Feature description
default_compress_func	It is used to set the default compression algorithm for table data. You can also specify other compression algorithms when creating a table.
default_compress	Specifies the default compression strategy to use when creating tables in Oracle-compatible mode.
tableapi_transport_compress_func	This API is used to set the compression algorithm for transmitting query results of tableAPI.
default_transport_compress_func	Sets the RPC compression algorithm for the entire cluster.

Parameter name	Feature description
enable_major_freeze	Specifies whether to enable automatic global freeze.
micro_block_merge_verify_level	Sets the verification level for macroblocks during major compaction.
row_compaction_update_limit	Specifies the number of modifications required to trigger in-memory major compaction for row data.
enable_global_freeze_trigger	Specifies whether to enable automatic global freeze.
enable_merge_by_turn	Specifies whether to enable the rolling compaction strategy.
enable_manual_merge	Specifies whether to enable manual major compaction.
global_major_freeze_residual_memory	The remaining memory threshold for triggering a global freeze. When the remaining memory drops below this percentage, a global freeze is triggered.
minor_deferred_gc_time	Sets the time interval for delayed SSTable reclamation after a major compaction.
zone_merge_concurrency	Specifies the number of zones that can concurrently perform major compactions during a major compaction. When the value is 0, the system automatically determines the optimal concurrency based on the deployment.
zone_merge_order	Specifies the rotation order for major compactions in zones. If not specified, the system automatically determines the order.
zone_merge_timeout	Sets the major compaction timeout for a single zone.
minor_freeze_times	25200.minor_freeze_times.md
minor_merge_concurrency	Specifies the number of concurrent threads during minor compactions.
minor_warm_up_duration_time	Sets the warm-up time for minor compactions that generate new minor compaction files.
row_purge_thread_count	Sets the maximum number of worker threads for in-row data merging in execution memory.

Parameter name	Feature description
ob_startup_mode	Specifies the startup mode of the OBServer node. This parameter can be modified only during the first startup.

Parameter name	Feature description
external_kms_info	Used to store key management information.
tde_method	Specifies the method for setting up transparent tablespace encryption.
audit_sys_operations	Specifies whether to track the operation behavior of system users.
audit_trail	Specifies whether to enable database auditing.

Parameter name	Feature description
cpu_quota_concurrency	Sets the maximum number of concurrent tasks allowed for each CPU quota of a tenant.

Parameter name	Feature description
enable_monotonic_weak_read	Specifies whether to enable monotonic read.
query_response_time_stats	Used to set whether to enable`information_schema.QUERY_RESPONSE_TIME`Statistics collection for views.
query_response_time_flush	Used to set whether to refresh.`information_schema.QUERY_RESPONSE_TIME`View and reread`query_response_time_range_base`.
query_response_time_range_base	Used to set`information_schema.QUERY_RESPONSE_TIME`The interval for collecting time parameters in the view.

Parameter name	Feature description
balancer_idle_time	The idle thread wake-up interval for background tasks such as load balancing.
enable_rebalance	It specifies whether to enable automatic load balancing.
enable_transfer	Specifies whether to allow data transfer within a tenant. If this parameter is disabled, data transfer between tenants is not allowed.`enable_rebalance`This parameter is invalid.
partition_balance_schedule_interval	The partition balancing scheduling cycle.

Parameter name	Feature description
log_restore_concurrency	Sets the concurrency for log restore.
log_archive_concurrency	Sets the concurrency for log archiving.
backup_data_file_size	Specifies the maximum file size for a single data backup file.

Parameter name	Feature description
max_partition_num	Controls the maximum number of partitions allowed in MySQL-compatible mode.

Parameter name	Feature description
ddl_thread_score	Specifies the number of threads used by the DDL task.
compaction_low_thread_score	Specifies the number of worker threads for low-priority compaction.
compaction_high_thread_score	Specifies the number of worker threads for high-priority compaction.
compaction_mid_thread_score	Specifies the number of worker threads for medium-priority compaction.
ha_high_thread_score	Sets the current number of worker threads for high-priority threads in high-availability mode.
ha_mid_thread_score	Sets the number of worker threads for priority threads in high availability mode.
ha_low_thread_score	Sets the current number of worker threads for high-availability low-priority threads.
ob_compaction_schedule_interval	The time interval for setting the Compaction scheduling.
compaction_dag_cnt_limit	Specifies the maximum number of DAGs allowed in the compaction DAG queue.
compaction_schedule_tablet_batch_cnt	Specifies the maximum number of partitions to be scheduled in each batch during compaction scheduling.
tenant_sql_login_thread_count	Sets the number of threads for MySQL tenant login. That is,`mysql_queue`Number of threads. The default value of 0 indicates to take the maximum number allowed by the operating system.`unit_min_cpu`The value of .
tenant_sql_net_thread_count	Sets the number of I/O threads for a MySQL-compatible tenant, that is,`sql_nio_server`Number of threads. The default value of 0 indicates to take all available threads.`unit_min_cpu`The value of .

Parameter name	Feature description
io_category_config	It specifies the percentages of I/O requests for each category.

Parameter name	Feature description
enable_sql_extension	Specifies whether to enable the SQL extension feature for the tenant.
compatible	This parameter is used to control the compatibility behavior of related features under a tenant and cannot be set.

Parameter name	Feature description
ob_proxy_readonly_transaction_routing_policy	Controls whether the proxy's routing for transactions is affected by read-only statements.

Parameter name	Feature description
lob_enable_block_cache_threshold	Sets the threshold for caching LOB queries stored in OUTROW format.

Parameter name	Feature description
rpc_memory_limit_percentage	Sets the maximum memory for RPCs in a tenant as a percentage of the tenant's total memory.
range_optimizer_max_mem_size	The memory used by the Query Range module.

Parameter name	Feature description
enable_kv_ttl	Controls whether to start the TTL background task. This parameter takes effect for periodic TTL tasks, but user management commands are not restricted by this setting. Note: The Time-To-Live (TTL) feature is limited to OceanBase Key-Value scenarios and is disabled in SQL scenarios. Otherwise, it may cause unexpected data deletion.
kv_ttl_duty_duration	Set the daily scheduled TTL trigger period. The TTL task is triggered once within this period.
kv_ttl_history_recycle_interval	Specifies the retention period for historical TTL task records.
ttl_thread_score	Sets the weight value for the thread time slice used by the TTL task.

Parameter name	Feature description
plsql_code_type	Specifies the compilation type for PL/SQL code.
plsql_debug	Specifies whether to compile the program into a debug version.
plsql_optimize_level	Specifies the compilation optimization level.
plsql_v2_compatibility	Specifies the compatibility features for Oracle 8.
plsql_warnings	It is used to control the error behavior of the PL/SQL compiler. You can specify a type or a`warning`The status of the code is`enable`、`disable`or`error`.

Parameter name	Feature description
enable_early_lock_release	Specifies whether to enable the pre-row lock release feature.
workarea_size_policy	Sets the strategy for manually or automatically adjusting the SQL workspace size.
open_cursors	Limits the number of cursors that a single session can open at the same time.
ob_ssl_invited_common_names	Records the list of application identities running under the current tenant. These identities are derived from the client-side certificates used in SSL mutual authentication.`subject`in the`cn`Field (common name).
ob_enable_batched_multi_statement	It is used to set whether to enable batch processing for grouped execution optimization.
job_queue_processes	It specifies the maximum number of tasks that can run concurrently for each tenant, with the aim of controlling task-induced resource consumption by tenants.
default_auto_increment_mode	Sets the default auto-increment mode for auto-increment columns.
ob_query_switch_leader_retry_timeout	Sets the maximum retry time for failed queries, in microseconds (us).
default_enable_extended_rowid	Specifies whether to create the table in extended ROWID mode.
dump_data_dictionary_to_log_interval	It is used to control the persistence cycle of tenant data dictionaries.
enable_user_defined_rewrite_rules	A switch for controlling whether user-defined rules are enabled.

Parameter name	Feature description
log_disk_utilization_limit_threshold	Sets the threshold for the tenant log disk usage limit. When the tenant's log disk usage exceeds the total log disk space of the tenant multiplied by this value, no further log writes are allowed.
log_disk_utilization_threshold	Sets the threshold for tenant log disk usage. When a tenant's log disk usage exceeds the total tenant log disk space multiplied by this value, log file reuse is performed.
writing_throttling_maximum_duration	The write speed is controlled by managing the memory allocation progress. Specifically, it specifies the time required to allocate the remaining MemStore memory after the write throttling is triggered.
writing_throttling_trigger_percentage	The threshold for setting the write speed.
standby_db_fetch_log_rpc_timeout	Specifies the RPC timeout period for log pulling from the standby database. This setting controls how quickly the standby database's log transfer service detects an unavailable primary server and switches to another one.
log_disk_throttling_percentage	The percentage of unreclaimable log disk space that triggers the log write throttling.
log_transport_compress_all	Specifies whether to compress log data during transmission.
log_transport_compress_func	A compressor used for log transmission.
clog_max_unconfirmed_log_count	Sets the maximum number of uncommitted logs allowed in the transaction module.
clog_persistence_compress_func	Sets the compression algorithm for transaction log persistence.
enable_clog_persistence_compress	Specifies whether to enable compression for transaction log persistence on disk.
log_storage_compress_all	Controls whether to enable clog storage compression.
log_storage_compress_func	Specifies the compression algorithm used for compressing stored clogs.

Parameter name	Feature description
log_disk_throttling_maximum_duration	This parameter specifies the maximum available time for the log disk after log throttling is triggered.
ls_gc_delay_time	Specifies the time after which a tenant's log stream will be deleted.
standby_db_preferred_upstream_log_region	Specifies the preferred region for log synchronization from the primary tenant to the standby tenant in a physical standby scenario.
archive_lag_target	Specifies the time delay for tenant log archiving.

Parameter name	Feature description
connection_control_failed_connections_threshold	Specifies the threshold for user incorrect login attempts.
connection_control_min_connection_delay	Specifies the minimum duration for which a user account is locked after exceeding the number of failed login attempts.
connection_control_max_connection_delay	Specifies the maximum duration for lockout after an incorrect login attempt. Once the duration reaches this maximum, it will no longer increase.

Parameter name	Feature description
default_progressive_merge_num	Sets the default number of progressive major compactions for a newly created table.
major_freeze_duty_time	Sets the trigger time for daily scheduled freezing and major compaction.
major_compact_trigger	Specifies the number of freezes that trigger a major compaction.
minor_compact_trigger	The threshold for the number of SSTables that triggers a minor compaction.
undo_retention	Specifies the duration for which multi-version data should be retained in seconds. This parameter controls the recycling of multi-version data during a minor compaction.
merger_check_interval	Sets the scheduling interval for the major compaction status-check thread.
freeze_trigger_percentage	Sets the memory usage threshold for tenants that triggers a global freeze.
max_kept_major_version_number	Specifies the number of frozen versions to retain for data retention.
merge_stat_sampling_ratio	Sets the sampling rate for data column statistics during major compaction.
merge_thread_count	Specifies the number of threads used for daily major compaction.
merger_completion_percentage	It is used to set the percentage threshold for the number of replicas completed with major compaction. When this threshold is reached, the scheduling for the current round of major compaction is considered complete.
merger_switch_leader_duration_time	Specifies the time interval for batch leader switchover during daily major compaction.
merger_warm_up_duration_time	This parameter specifies the warm-up time for the new baseline data during major compaction.

Parameter name	Feature description
arbitration_timeout	Specifies the timeout period for triggering automatic downgrade.

Parameter name	Feature description
sql_work_area	Sets the workspace memory for a tenant.
max_stale_time_for_weak_consistency	This parameter specifies how old data is allowed to be read in weak-consistency reads.

OceanBase

Customer Stories

Documentation

Parameter overview

Cluster-level parameters

Security

Backup and Recovery

Load balancing

Disaster recovery tasks

Partitioning

Backend Execution Threads

Memory space

Others

Root Service

RPC Authentication

SQL

Transactions and transaction logs

Debugging

System logs

Compression Algorithms

Tenant-level parameters

Security

Read/Write and Query

Load balancing

Backup and Recovery

Partitioning

Backend Execution Threads

Compatibility

Note

Routing

LOB data

Memory space

OBKV

Others

Transactions and transaction logs

System logs

Note

Arbitration Service

Unsupported parameters

OceanBase

Customer Stories

Documentation

Parameter overview

Cluster-level parameters

Security

Backup and Recovery

Cgroup related

CPU-related

DBlink related

Read/write/query related

Load balancing

Disaster recovery tasks

Replica-related

Cache-related

Partitioning

Backend Execution Threads

I/O-related

Cluster-related

Bandwidth-related

Location cache related

Directory path related

Memory space

PX-related

Others

Root Service

RPC Authentication

SQL

Transactions and transaction logs

Lock-related

Debugging

TCP-related

System logs

Compression Algorithms

Minor compaction and major compaction related

Arbitration service related

Tenant-level parameters

Security

CPU-related

Read/Write and Query

Load balancing

Backup and Recovery

Partitioning

Backend Execution Threads

I/O-related

Compatibility

Note

Routing

LOB data

Memory space

OBKV

PL-related

Others

Transactions and transaction logs

System logs

User login

Note

Minor compaction and major compaction related

Arbitration Service

Unsupported parameters