Overview|V4.2.0| docs|Distributed Database

Parameter	Description
enable_ob_ratelimit	Enables bandwidth throttling between regions in RPC connections.
ob_ratelimit_stat_period	The interval for calculating and updating the maximum bandwidth of an OBServer node.

Parameter name	Description
balancer_log_interval	The interval for load balancing and other background tasks to print statistics logs.
balancer_task_timeout	The timeout period for load balancing and other background tasks.
balancer_tolerance_percentage	The tolerance level for disk imbalance among units within a tenant in a load balancing strategy. If the disk imbalance is within the tolerance level, an equilibrium action is not triggered.
server_balance_critical_disk_waterlevel	The water level for triggering the disk space load balancing feature.
server_balance_disk_tolerance_percent	The tolerance level for disk load imbalance among nodes in a load balancing strategy.
resource_hard_limit	The unit allocation strategy.
enable_sys_unit_standalone	Specifies whether to isolate system tenant units on a node.

Parameter name	Description
enable_rereplication	Specifies whether to enable the automatic resynchronization feature.
ls_meta_table_check_interval	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	The timeout period for changing the Paxos member group during replica migration.
sys_bkgd_migration_retry_num	The maximum number of retries when replica migration fails.

Parameter name	Description
backup_data_file_size	The maximum file size of a single data backup file.
log_restore_concurrency	The concurrency level for restoring logs.

Parameter name	Description
all_server_list	Displays the addresses of all servers in the cluster.
cluster	Sets the name of the OceanBase cluster.
cluster_id	Sets the ID of the OceanBase cluster.
rpc_timeout	Sets the timeout period for internal requests in the cluster.
local_ip	The IP address of the server where ObServer is installed.
observer_id	A unique identifier assigned to the OBServer node by the cluster.

Parameter name	Description
sql_login_thread_count	The number of threads for processing SQL login requests.

Parameter name	Description
cpu_count	The total number of CPU cores in the system. If set to 0, the system will automatically detect the number of CPU cores.
server_balance_cpu_mem_tolerance_percent	The tolerance for CPU and memory resource imbalance in node load balancing.
server_cpu_quota_max	The maximum CPU quota available to the system.
server_cpu_quota_min	The minimum CPU quota available to the system, which will be automatically reserved.
token_reserved_percentage	The percentage of idle tokens reserved for a tenant during CPU scheduling in the control tenant.
workers_per_cpu_quota	The number of worker threads allocated to each CPU quota.

Parameter name	Description
config_additional_dir	Multiple directories for storing configuration files for redundancy.

Parameter name	Description
datafile_disk_percentage	The percentage of total space on the disk where the data_dir is located. The OceanBase Database system initializes the data_dir disk to store data.
data_disk_usage_limit_percentage	The maximum percentage of data files that can be written. After this threshold is reached, data migration is prohibited.
enable_sql_operator_dump	Specifies whether to allow intermediate results of SQL processing to be written to disk to free up memory.
global_write_halt_residual_memory	The threshold of residual memory in bytes, in decimal, for triggering the halt of write requests for normal tenants (`sys` tenant is not affected).
leak_mod_to_check	Specifies the memory leak check module. This parameter is for internal debugging.
memory_chunk_cache_size	The capacity of memory chunks cached in the memory allocator.
memory_limit	The total size of available memory.
memory_limit_percentage	The percentage of total memory size that is available to the system.
memory_reserved	The size of memory reserved for the KVCache.
memstore_limit_percentage	The maximum percentage of memory used by MemStores in a tenant out of its total available memory.
system_memory	The size of memory reserved for the tenant with ID `500`.
use_large_pages	The management of large pages used by the database.

Parameter name	Description
debug_sync_timeout	The timeout period of the Debug Sync feature.
enable_rich_error_msg	Specifies whether to add debugging information, such as the server address, timestamp, and trace ID, to client messages.

Parameter name	Description
default_compress_func	The default compression algorithm for table data. You can also specify a different compression algorithm when you create a table.
default_compress	The default compression strategy for tables in Oracle mode when you create a table.
tableapi_transport_compress_func	The compression algorithm for transmitting query results of tableAPI.

Parameter name	Description
log_disk_size	The size of the redo log disk.
log_disk_percentage	The maximum percentage of space that redo logs can occupy on a disk.
clog_sync_time_warn_threshold	The sync time threshold for generating a warning log. A sync time exceeding this threshold triggers a WARN log.
dtl_buffer_size	The size of the buffer used by the SQL data transmission module.
ignore_replay_checksum_error	Specifies whether to ignore checksum errors encountered during transaction log replay.
trx_2pc_retry_interval	The interval for automatic retries after a two-phase commit failure.

Parameter name	Description
enable_major_freeze	Specifies whether to enable the automatic global freeze feature.
micro_block_merge_verify_level	The verification level of macroblocks during a minor compaction.
row_compaction_update_limit	The number of updates of in-memory intra-row data triggering a minor compaction.

Parameter	Description
px_workers_per_cpu_quota	The ratio of the number of parallel execution worker threads to the number of CPU cores.
px_task_size	The size of data processed by each task of the SQL parallel query engine.
max_px_worker_count	The maximum number of threads used by the SQL parallel query engine.

Parameter name	Description
bf_cache_miss_count_threshold	The number of times a macroblock must be missed in the Bloomfilter Cache for the cache to be created.
bf_cache_priority	The priority of the Bloom Filter cache.
cache_wash_threshold	The capacity threshold that triggers cache cleanup.
fuse_row_cache_priority	The priority of the Fusion Row cache in the cache system.
user_row_cache_priority	The priority of the baseline data row cache in the cache system.
autoinc_cache_refresh_interval	The refresh interval of the auto-increment column cache.
plan_cache_evict_interval	The interval at which the execution plan cache is cleared.
index_block_cache_priority	The priority of the metadata index microblock cache.
opt_tab_stat_cache_priority	The priority of the statistics cache.
tablet_ls_cache_priority	The priority of the tablet mapping cache.
user_block_cache_priority	The priority of the data block cache in the cache system.

Parameter name	Description
virtual_table_location_cache_expire_time	The expiration time of the location information cache for virtual tables.
location_cache_refresh_rpc_timeout	The timeout period of refreshing the `location_cache` table through RPC.
location_cache_refresh_sql_timeout	The timeout period of refreshing the `location_cache` table through SQL.
location_cache_refresh_min_interval	The minimum interval between location cache refresh requests to prevent excessive refresh requests from causing high system pressure.
location_cache_cpu_quota	The CPU quota for the location cache module.
location_fetch_concurrency	The maximum number of concurrent refreshes of the location cache on a single server.
location_refresh_thread_count	The number of threads on an OBServer node for requesting partition location information from the Root Service.

Parameter name	Description
enable_record_trace_log	Specifies whether to record trace logs.
enable_async_syslog	Specifies whether to enable asynchronous write of system logs.
enable_syslog_recycle	Specifies whether to enable the recycle of system logs.
enable_syslog_wf	Specifies whether to write trace logs of the WARN level and higher to a separate log file.
max_string_print_length	The maximum length of a single line in a system log.
max_syslog_file_count	The maximum number of log files that can be accommodated before the files are recycled.
syslog_level	The system log level.
trace_log_sampling_interval	The time interval for periodically recording trace logs.

Parameter name	Description
tablet_meta_table_check_interval	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	The number of tablets cached in memory during iteration of the tablet meta table.
tablet_size	The size of each shard for internal parallel processing (such as major compactions and queries) in a partition.

Parameter name	Description
weak_read_version_refresh_interval	The refresh interval for weak-consistency read versions, which affects the latency of weak-consistency read data.
large_query_worker_percentage	The percentage of worker threads reserved for handling large queries.
large_query_threshold	The execution time threshold for identifying a large query.
trace_log_slow_query_watermark	The execution time threshold for identifying a slow query. A trace log of a slow query is written to system logs.

Parameter name	Description
rootservice_async_task_queue_size	The size of the asynchronous task queue in Root Service.
rootservice_async_task_thread_count	The size of the thread pool for asynchronous tasks in Root Service.
rootservice_list	The list of servers where Root Service and its replicas reside.
rootservice_ready_check_interval	The time interval for checking the cluster status after Root Service starts.
rootservice_memory_limit	The maximum memory capacity allowed to Root Service.
lease_time	The lease duration for heartbeats.
server_check_interval	The interval for checking the consistency of the server table.
server_permanent_offline_time	The time threshold for determining a permanently offline node. After a node is deemed permanently offline, its data replicas need to be automatically supplemented.
ob_event_history_recycle_interval	The interval for recycling historical events.

Parameter name	Description
rdma_io_thread_count	The number of I/O threads for RDMA.
syslog_io_bandwidth_limit	The maximum disk I/O bandwidth allowed for system logs. Excess system logs will be discarded.
disk_io_thread_count	The number of I/O threads for disks. It must be an even number.
net_thread_count	The number of I/O threads for networks.

Parameter name	Description
enable_tcp_keepalive	Specifies whether to enable the keepalive mechanism for client connections.
tcp_keepidle	The time in seconds after a client connection is established with the server that no data is sent before a keepalive probe is sent.
tcp_keepintvl	The time interval in seconds between two keepalive probes when the keepalive mechanism is enabled.
tcp_keepcnt	The maximum number of retries before a non-active connection is closed when the keepalive mechanism is enabled.

Parameter	Description
rpc_client_authentication_method	The RPC client's secure authentication method.

Parameter name	Description
builtin_db_data_verify_cycle	The period for self-inspection of bad data blocks, in days. The value 0 specifies not to perform the inspection.
data_storage_warning_tolerance_time	The tolerance period for a data disk to be in the WARNING state.
dead_socket_detection_timeout	The interval for detecting failed sockets.
enable_sys_table_ddl	Specifies whether to allow manual creation of system tables.
internal_sql_execute_timeout	The interval for system internal DML requests.
migration_disable_time	The duration of suspending data migration to the failed node when the node's data migration fails due to a full disk.
schema_history_expire_time	The expiration time of metadata history data.
datafile_size	The size of data files. Generally, you do not need to set this parameter.
devname	The name of the network card to which the service process binds.
enable_perf_event	Specifies whether to enable the collection of performance events.
enable_record_trace_id	Specifies whether to record the trace IDs set by applications.
enable_upgrade_mode	Specifies whether to enable upgrade mode. In upgrade mode, some system background features are suspended.
enable_ddl	Specifies whether to allow DDL operations.
high_priority_net_thread_count	The number of high-priority network threads. The value `0` specifies to disable this feature.
mysql_port	The port number for the SQL service protocol.
obconfig_url	The URL address of the OBConfig service.
rpc_port	The port number for remote access.
ssl_client_authentication	Specifies whether to enable the SSL connection feature.
stack_size	The size of the call stack of a program function.
tenant_task_queue_size	The size of the request queue of each tenant.
zone	The name of the zone to which the node belongs. Generally, you do not need to set this parameter.
ssl_external_kms_info	Records some information on which the SSL feature of OceanBase Database depends. It records relevant configurations for different SSL modes in the JSON format. The JSON record contains at least the `ssl_mode` field.
recyclebin_object_expire_time	Automatically purges expired schema objects from the recycle bin.
default_row_format	The default row format when creating a table in MySQL mode.
enable_sql_audit	Specifies whether to enable SQL auditing.
min_observer_version	The application version number of the minimum OBServer node in the cluster.
sys_bkgd_net_percentage	The percentage of network bandwidth available to background system tasks.
schema_history_recycle_interval	The interval for recycling `schema` multi-version records in the system.
enable_asan_for_memory_context	When using ob_asan, specifies whether to allow ObAsanAllocator (default ObAllocator as the MemoryContext allocator) to be used.

Parameter name	Description
plan_cache_high_watermark	The threshold of memory usage of the execution plan cache. When the memory usage exceeds this threshold, automatic plan eviction is triggered.
plan_cache_low_watermark	The threshold of memory usage of the execution plan cache. When the memory usage falls below this threshold, plan eviction is stopped.
tenant_cpu_variation_per_server	The allowed deviation of CPU quota scheduling among multiple units of a tenant.
system_trace_level	The log level of system tracing logs.

Parameter	Description
connection_control_failed_connections_threshold	The threshold of failed login attempts.
connection_control_min_connection_delay	The minimum duration of account lockout after the failed login attempt threshold is reached.
connection_control_max_connection_delay	The maximum duration of account lockout. The account lockout duration does not increase after it reaches the maximum duration.

Parameter	Description
balancer_idle_time	The interval at which the load balancing thread is awakened when it is idle.
enable_rebalance	Specifies whether to enable automatic load balancing.

Parameter	Description
audit_sys_operations	Specifies whether to track the operations of system users.
audit_trail	Specifies whether to enable database audit.

Parameter name	Description
log_disk_utilization_limit_threshold	The threshold of log disk utilization for limiting log write. When the usage of the log disk exceeds the total size of the log disk space of the tenant multiplied by this threshold, log write is no longer allowed.
log_disk_utilization_threshold	The threshold of log disk utilization for log file reuse. When the usage of the log disk exceeds the total size of the log disk space of the tenant multiplied by this threshold, log file reuse is performed.
writing_throttling_maximum_duration	Controls the write speed by controlling memory allocation. Specifically, it specifies the time required for allocating the remaining MemStore memory after write throttling is triggered.
writing_throttling_trigger_percentage	The threshold of write speed.

Configuration Item Name	Function Description
default_progressive_merge_num	Used to set the default number of progressive merges when creating a new table.
major_freeze_duty_time	Used to set the trigger time for daily scheduled freezing and merging.
major_compact_trigger	Used to set how many freezes trigger a merge.
minor_compact_trigger	The threshold for the number of SSTables that triggers a dump (Minor Compaction).
undo_retention	Used to set the range of multi-version data that the system should retain, in seconds, controlling the recycling of multi-version data during dumping.
merger_check_interval	Used to set the scheduling interval for the merge status check thread.
freeze_trigger_percentage	Used to set the tenant memory usage threshold for triggering global freezing.

Configuration Item Name	Function Description
cpu_quota_concurrency	Used to set the maximum concurrency allowed for each CPU quota of a tenant.

Parameter name	Description
external_kms_info	Stores some key management information.
tde_method	Specifies the method for transparently encrypting tablespaces.

Parameter name	Description
plsql_code_type	Specifies the compilation type of PL/SQL code.
plsql_debug	Specifies whether to compile a debug version.
plsql_optimize_level	Specifies the optimization level during compilation.
plsql_v2_compatibility	Specifies compatibility features from Oracle 8. Notice This parameter applies only to Oracle mode and is currently not in effect.

Configuration item	Description
enable_sql_extension	Specifies whether to enable SQL extensions for the tenant.

Configuration item	Description
enable_monotonic_weak_read	Specifies whether to enable monotonic reads.
query_response_time_stats	Specifies whether to enable statistics collection for the `information_schema.QUERY_RESPONSE_TIME` view.
query_response_time_flush	Specifies whether to flush the `information_schema.QUERY_RESPONSE_TIME` view and re-read `query_response_time_range_base`.
query_response_time_range_base	The interval for the time parameter in the `information_schema.QUERY_RESPONSE_TIME` view to collect statistics.

Configuration item	Description
ob_proxy_readonly_transaction_routing_policy	Controls whether the Proxy takes read-only statements into account when routing transactions.

Parameter name	Description
io_category_config	The percentage of I/O requests for each category.

Parameter name	Description
compaction_low_thread_score	The number of worker threads for low-priority compactions.
compaction_high_thread_score	The number of worker threads for high-priority compactions.
compaction_mid_thread_score	The number of worker threads for medium-priority compactions.
ha_high_thread_score	The number of worker threads for high-priority threads of high availability.
ha_mid_thread_score	The number of worker threads for medium-priority threads of high availability.
ha_low_thread_score	The number of worker threads for low-priority threads of high availability.
ob_compaction_schedule_interval	The scheduling interval for compactions.

Parameter name	Description
enable_early_lock_release	Specifies whether to enable the early lock release feature.
workarea_size_policy	Specifies the strategy for adjusting the size of the SQL workspace, which can be manual or automatic.
open_cursors	Specifies the maximum number of cursors that can be opened simultaneously in a session.
ob_ssl_invited_common_names	Records the application identities of the tenant, which are from the `cn` field (common name) in the `subject` field of the client certificate during two-way SSL authentication.
ob_enable_batched_multi_statement	Specifies whether to enable the grouped execution optimization for the batch processing feature.
job_queue_processes	The maximum number of jobs that can run simultaneously for a tenant. This parameter is used to control the extent to which jobs can monopolize the resources of the tenant. Notice This parameter takes effect only in Oracle mode.
default_auto_increment_mode	Specifies the default auto-increment mode.
ob_query_switch_leader_retry_timeout	The maximum retry duration for failed queries, in microseconds (us).
default_enable_extended_rowid	Specifies whether to create a table in the extended ROWID mode by default.

Configuration item name	Description
sql_work_area	The size of memory for the tenant's workspace.
max_stale_time_for_weak_consistency	The maximum allowed age of data for weak-consistency reads.

Overview

Cluster-level parameters

Others

Unsupported parameters

Tenant-level parameters

Note

Minor and major compactions

CPU

Encryption

PL

Note

Background execution threads

Others

Unsupported configuration items

Overview

Cluster-level parameters

Bandwidth-related

Load balancing-related

Synchronization-related

Backup and restore-related

Cluster-related

SQL-related

CPU-related

Directory path-related

Memory space-related

Debugging-related

Compression algorithm-related

Transaction and transaction log-related

Minor and major compaction-related

PX-related

Cache-related

Location Cache-related

Log-related

Partition-related

Read/write and query-related

Root Service-related

I/O-related

TCP-related

RPC authentication-related

Others

Unsupported parameters

Tenant-level parameters

User login-related

Note

Load balancing-related

Audit-related

Transaction and transaction log-related

Minor and major compactions

CPU

Encryption

PL

Compatibility-related

Note

Read/write and query-related

Routing-related

I/O-related

Background execution threads

Others

Unsupported configuration items