This topic describes the cluster-level and tenant-level parameters of OceanBase Database in detail based on their functions.
Cluster-level parameters
Security-related
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 SSL/TLS protocol version to be used for SSL connections of SQL statements. |
| ssl_client_authentication | Specifies whether to enable the SSL connection feature. |
| ssl_external_kms_info | Used to record information required for the operation of the SSL feature in OceanBase Database. It records the configuration dependencies for different SSL usage methods in a JSON string format. The JSON must contain at least the typessl_modefield. |
| enable_sql_audit | Specifies whether to enable the SQL audit feature. |
Backup and recovery-related
Parameter name |
Feature description |
|---|---|
| backup_backup_dest | Specifies the backup destination for the backup data. |
| backup_backup_dest_option | Parameters related to backup control. |
| backup_dest_option | Parameters for controlling backup operations. |
| backup_concurrency | Specifies the concurrency level for writing 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 | Controls the maximum memory usage of a single node for log archiving. |
| log_archive_checkpoint_interval | Specifies the time interval for checking log archiving of cold data. |
| restore_concurrency | Sets the maximum concurrency for restoring tenant data from a backup. |
cgroup-related
Parameter name |
Feature description |
|---|---|
| enable_cgroup | It is used to control whether the cgroup feature is enabled for the OBServer node. |
CPU-related
Parameter name |
Feature description |
|---|---|
| cpu_count | Specifies the total number of system CPUs. If you set this parameter to 0, the system automatically detects the number of CPUs. |
| server_balance_cpu_mem_tolerance_percent | In the node load balancing strategy, this parameter specifies the tolerance for CPU and memory resource imbalances. |
| server_cpu_quota_max | Sets the maximum CPU quota available for the system. |
| 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 | Specifies the number of worker threads allocated to each CPU. |
| cpu_reserved | It 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 | Sets the CPU utilization threshold. When the CPU utilization exceeds this threshold, the system will pause the execution of background tasks. |
| system_cpu_quota | Sets the CPU quota available to the sys tenant. |
| tenant_cpu_variation_per_server | It specifies the allowable deviation for CPU quota scheduling among multiple units of a tenant. |
Read/write/query-related
Parameter name |
Feature description |
|---|---|
| weak_read_version_refresh_interval | Sets the refresh interval for weak-consistency read version numbers, 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 | The threshold for setting the 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. |
Load balancing-related
Parameter name |
Feature description |
|---|---|
| balancer_log_interval | Sets the interval for printing statistical logs by the threads of a disaster recovery task. |
| balancer_task_timeout | This parameter specifies 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 up to this tolerance, no balancing action is triggered. |
| server_balance_critical_disk_waterlevel | The watermarks used to set the load balancing function for 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 | Specifies whether the unit of the system tenant is exclusive to a node. |
| balancer_emergency_percentage | It is used to set the unit load threshold. When the unit load exceeds this threshold, replica migration out is allowed, and load balancing is performed even during major compaction. |
| balancer_timeout_check_interval | Sets the timeout interval for checking background tasks such as load balancing. |
| data_copy_concurrency | Sets the maximum number of concurrently executing data migration replication tasks 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. |
Replica-related
Parameter name |
Feature description |
|---|---|
| unit_gc_wait_time | Specifies the maximum wait time for a unit GC. If the GC does not start within this period, it is forced. |
| enable_rereplication | The master switch for automatic migration and replication of log stream replicas. |
| ls_meta_table_check_interval | This parameter specifies the check interval for the background inspection thread of the DBA_OB_LS_LOCATIONS or 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 | Sets the threshold for the number of consecutive failures of 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 added to the blacklist. |
| election_cpu_quota | This parameter specifies the CPU quota allocated to 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 being revoked. |
| 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 building each replica when creating a global index. |
| get_leader_candidate_rpc_timeout | Sets the internal request timeout period for obtaining candidates in automatic leader switchover. |
| migrate_concurrency | Sets the maximum concurrency for internal data migration. |
| rebuild_replica_data_lag_threshold | Sets 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 from a single node. |
| replica_safe_remove_time | Specifies the maximum period for which deleted replicas can be retained before cleanup. |
Cache-related
Parameter name |
Feature description |
|---|---|
| bf_cache_miss_count_threshold | It specifies the number of misses required before a Bloomfilter cache is created for a macroblock. |
| bf_cache_priority | Used to set the Bloom filter cache priority. |
| cache_wash_threshold | Sets 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 | Specifies the eviction interval for the execution 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 tablet mapping cache priority. |
| user_block_cache_priority | Sets the priority of a data block cache in the caching system. |
| index_info_block_cache_priority | Sets the cache 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 cache priority for storing statistics in the caching system. |
| plan_cache_high_watermark | The threshold for the memory occupied by the plan cache. When the memory 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. |
Partition-related
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 | This parameter 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 compaction and query execution) within a partition. |
| auto_broadcast_location_cache_rate_limit | Sets the maximum number of partitions whose location information 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 automatic 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 for the partition. |
| partition_table_check_interval | It specifies the time interval for an OBServer node to delete non-existent replicas from a partitioned table. |
Background execution thread-related
Parameter name |
Feature description |
|---|---|
| sql_net_thread_count | It specifies the number of I/O threads in a MySQL cluster.global_sql_nio_serverThe number of threads. The default value is 0, which means to use the value specified by the parameternet_thread_counthave the same value. |
| auto_leader_switch_interval | Sets the working interval time for the automatic leader switchover background thread. |
| switchover_process_thread_count | Sets the size of the thread pool related to primary/standby switchover. |
I/O-related
Parameter name |
Feature description |
|---|---|
| sync_io_thread_count | Configures the number of threads for synchronizing I/O requests. |
| syslog_io_bandwidth_limit | This parameter specifies the upper limit of disk I/O bandwidth that system logs can occupy. System logs exceeding this bandwidth limit will be discarded. |
| disk_io_thread_count | Specifies the number of threads for disk I/O. The value 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 be set asERRORThe 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 | Sets the minimum percentage of system background I/O usage. |
| user_iort_up_percentage | This parameter is used to set the user disk I/O latency threshold. When the user disk I/O latency exceeds this threshold, the system's background I/O tasks will be throttled. |
| ob_esi_rpc_port | Sets the communication port between the OBESE process and the OBSERVER process. |
| enable_ob_esi_process | It is used to control whether to enable the obesi (external storage interface) process. |
| ob_esi_session_timeout | Sets the timeout period for an obese process to hold 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 capacity of the block cache for a single I/O aggregate read. |
| multiblock_read_size | It specifies the I/O aggregation size for data reading. |
Cluster-related
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 | The ID of the current OceanBase cluster. |
| rpc_timeout | Sets the timeout period for internal requests within a 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 | A unique identifier for the RS allocated to an OBServer node in a cluster. |
| min_observer_version | Displays the minimum application version number of OBServer nodes in the cluster. |
Bandwidth-related
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 | Specifies the time interval for calculating and updating the maximum bandwidth on an OBServer node. |
Location Cache related
Parameter name |
Feature description |
|---|---|
| virtual_table_location_cache_expire_time | Sets the cache expiration time for the location information of virtual tables. |
| location_cache_refresh_rpc_timeout | Refresh via RPClocation_cacheThe timeout period. |
| location_cache_refresh_sql_timeout | Refresh via SQLlocation_cacheThe timeout period. |
| location_cache_refresh_min_interval | This parameter specifies the minimum interval for refreshing location cache requests to prevent excessive system pressure caused by too many refresh requests. |
| 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. |
Directory path related
Parameter name |
Feature description |
|---|---|
| config_additional_dir | Specifies multiple directories for storing the configuration file locally to ensure redundant storage of multiple configuration files. |
| data_dir | Specifies the directory for storing data such as SSTables. |
Memory space
Parameter name |
Feature description |
|---|---|
| datafile_disk_percentage | It indicates the percentage of the total space on the disk where data_dir is located that is occupied. The disk where data_dir resides will be initialized by the OceanBase database system for data storage. |
| data_disk_usage_limit_percentage | Specifies the maximum percentage of data files that can be written. When the usage exceeds this threshold, data migration in 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 | Used to set the trigger for pausing write operations of a user tenant (sysThe global remaining memory threshold (which does not affect tenants). |
| leak_mod_to_check | This feature is used for memory leak detection and is an internal debugging tool. |
| memory_chunk_cache_size | Specifies the memory block size cached by the memory allocator. |
| memory_limit | Indicates the total size of available memory. |
| memory_limit_percentage | Sets the percentage of total memory that the system's total available memory size occupies. |
| memory_reserved | This parameter specifies the memory size reserved for underlying system modules. |
| 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 to500The 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. |
PX-related
Parameter name |
Feature description |
|---|---|
| px_task_size | This parameter 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 used by the SQL parallel query engine. |
Others
Parameter name |
Feature description |
|---|---|
| builtin_db_data_verify_cycle | Specifies the self-check cycle for bad data blocks, in days. A value of 0 indicates no check. |
| data_storage_warning_tolerance_time | Specifies the tolerance period for allowing the data disk status to remain at WARNING. |
| dead_socket_detection_timeout | The time interval for detecting invalid sockets. |
| migration_disable_time | Specifies the duration for which data migration is paused when a node fails to migrate data in due to full disk or other reasons. |
| schema_history_expire_time | 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 NIC 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 operations. |
| ob_enable_utl_tcp | This parameter specifies whether to enable the UTL_TCP system package. |
| high_priority_net_thread_count | Sets the number of high-priority network threads. The value is0indicates that this feature is disabled. |
| obconfig_url | Sets 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 | Specifies the name of the zone where the node is located. This parameter is generally not required. |
| 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 | Sets the percentage of network bandwidth that background system tasks can occupy. |
| schema_history_recycle_interval | Used to set the internal execution of the system.schemaThe time interval for reclaiming records across multiple versions. |
| enable_asan_for_memory_context | When using ob_asan, this parameter specifies whether to allow ObAsanAllocator (by default, ObAllocator serves as the allocator for MemoryContext). |
| ofs_list | Stores the OFS (OceanBase File System, a distributed storage system independently designed by OceanBase Database) connection URL for each zone. It is primarily used to enable RootService to access files across zones in OFS deployment mode. |
| async_ps_cursor_max_count | Controls the maximum number of asynchronous PS cursors allowed on a single node. |
Log Service
Parameter name |
Feature description |
|---|---|
| enable_logservice | A switch to control the logging service mode. |
| logservice_access_point | Used to persist the log service access point. |
Root Service
Parameter name |
Feature description |
|---|---|
| rootservice_async_task_queue_size | Sets the size of the internal asynchronous task queue for the Root Service. |
| 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 reside. |
| rootservice_ready_check_interval | Specifies the interval for waiting and checking the cluster status after the root service starts. |
| rootservice_memory_limit | Sets the maximum memory capacity limit for the Root Service. |
| lease_time | Sets the duration of a heartbeat lease. |
| server_check_interval | Sets the time interval for consistency check of server tables. |
| server_permanent_offline_time | Sets 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 must be automatically replenished. |
| ob_event_history_recycle_interval | Specifies the interval for reclaiming historical events. |
| enable_rootservice_standalone | Specifies whether to allow the sys tenant and RootService to exclusively occupy OBServer nodes. |
| fast_recovery_concurrency | It is used to control the concurrency of 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 leader switchover commands for at a time. |
RPC Authentication
Parameter name |
Feature description |
|---|---|
| rpc_client_authentication_method | Sets the security authentication method for the RPC client. |
| rpc_server_authentication_method | This parameter specifies the security authentication method for the RPC server. |
SQL
Parameter name |
Feature description |
|---|---|
| sql_login_thread_count | Sets the number of threads for processing SQL login requests. |
| sql_audit_memory_limit | Specifies the maximum memory that SQL audit data can occupy. |
| enable_sys_table_ddl | Specifies whether manual creation of system tables is allowed. |
| internal_sql_execute_timeout | Sets the time interval for internal DML requests in the system. |
Transactions and transaction logs
Parameter name |
Feature description |
|---|---|
| log_disk_size | Specifies the size of the redo log disk. |
| log_disk_percentage | Sets the percentage of total disk space occupied by redo logs. |
| dtl_buffer_size | This parameter specifies the cache size for 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 a disk is marked as bad after failing to serve I/O requests from the log disk. This parameter determines when a leader switchover is triggered. |
| clog_disk_utilization_threshold | The threshold for controlling the reuse of disk space for clogs or ilogs. |
| clog_expire_days | 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 example shows you how to set the alert threshold for transaction log synchronization duration. A WARN log is generated when the synchronization duration exceeds this value. |
| clog_transport_compress_func | Sets 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 | This parameter specifies 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 transaction log indexes in the caching system. |
| ilog_index_expire_time | Sets the maximum time within which an OBServer can read an ILog file. |
| trx_force_kill_threshold | Specifies the maximum wait time for killing transactions when necessary due to freezing or leader switchover. |
Lock-related
Parameter name |
Feature description |
|---|---|
| trx_try_wait_lock_timeout | Specifies the wait duration for row locks during statement execution. |
Debugging
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 | Specifies whether to add server address, time, trace ID and other debugging information to client messages. |
TCP-related
Parameter name |
Feature description |
|---|---|
| enable_tcp_keepalive | Enables or disables the keep-alive mechanism for client connections. |
| tcp_keepidle | Specifies the interval, in seconds, after which a Keepalive probe 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 probes when the keep-alive mechanism for client connections is enabled. |
| tcp_keepcnt | Specifies the maximum number of retries before closing an inactive connection. |
External tables
Parameter name |
Feature description |
|---|---|
| external_table_disk_cache_max_percentage | This parameter specifies the maximum percentage of datafile_size that can be allocated to disk cache for external tables in SN mode. |
System logs
Parameter name |
Feature description |
|---|---|
| alert_log_level | The level of the alert log. |
| 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 log retention feature for OBServer nodes.max_syslog_file_countUsed together to determine whether the recycling logic should consider old log files. |
| enable_syslog_wf | Specifies whether to log system logs of WARN level and above to a separate log file. |
| max_string_print_length | Specifies the maximum length of a single line in system logs that can be printed. |
| max_syslog_file_count | Specifies the maximum number of log files that can be retained before log files are recycled. |
| syslog_level | Sets the system log level. |
| trace_log_sampling_interval | Specifies the time for regularly printing trace logs. |
| diag_syslog_per_error_limit | Specifies the maximum 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 log archiving. |
| system_trace_level | Sets the log level for system tracing logs. |
Compression Algorithms
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 | Sets the compression algorithm used for transmitting query results in OBKV-Table. |
| default_transport_compress_func | Sets the RPC compression algorithm for the entire cluster. |
Minor compaction and major compaction related
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. A global freeze is triggered when the remaining memory drops below this percentage. |
| minor_deferred_gc_time | This parameter specifies the time interval for delayed SSTable reclamation after a major compaction. |
| zone_merge_concurrency | Specifies the number of zones that can run concurrently during major compactions. When this parameter is set to 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 period for a single zone. |
| minor_freeze_times | Specifies the number of major compactions triggered by freezes. |
| minor_merge_concurrency | Specifies the number of concurrent threads during minor compactions. |
| minor_warm_up_duration_time | Sets the warm-up time for generating a new minor compaction file during a minor compaction. |
| row_purge_thread_count | Sets the maximum number of worker threads for in-row data merging in execution memory. |
Arbitration service
Parameter name |
Feature description |
|---|---|
| arbitration_degradation_policy | Specifies the automatic downgrade strategy. |
| ob_startup_mode | Specifies the startup mode of the OBServer node. This parameter can be modified only during the first startup. |
Resource isolation
Parameter name |
Feature description |
|---|---|
| clog_io_isolation_mode | Determines whether I/O requests to the clog disk are subject to resource isolation based on whether the clog disk and data disk are independent. |
| enable_global_background_resource_isolation | Enables global isolation of foreground and background resources. |
| global_background_cpu_quota | Controls the CPU quota for background tasks when global foreground-background resource isolation is enabled. |
Tenant-level parameters
Security-related
Parameter name |
Feature description |
|---|---|
| sts_credential | Specifies the credentials for accessing the STS service provided by OCP. |
| 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. |
Storage-related
Parameter name |
Feature description |
|---|---|
| default_table_organization | Specifies the default table organization mode for creating tables. |
| default_table_merge_engine | Specifies the default table creation parameters for user tenants.merge_engine. |
| default_delta_format | Specifies the default incremental data storage format when creating a table. |
CPU-related
Parameter name |
Feature description |
|---|---|
| cpu_quota_concurrency | It specifies the maximum number of concurrent tasks allowed for each CPU quota of a tenant. |
Read/write and query-related
Parameter name |
Feature description |
|---|---|
| enable_monotonic_weak_read | Specifies whether to enable monotonic read. |
| query_response_time_stats | Used to set whether to enableinformation_schema.QUERY_RESPONSE_TIMEStatistics collection for views. |
| query_response_time_flush | Used to set whether to refresh.information_schema.QUERY_RESPONSE_TIMEView and rereadquery_response_time_range_base. |
| query_response_time_range_base | Used to setinformation_schema.QUERY_RESPONSE_TIMEThe interval for collecting time parameters in the view. |
Load balancing-related
Parameter name |
Feature description |
|---|---|
| enable_ls_leader_balance | Controls whether to enable automatic leader balancing for log streams. |
| enable_gts_standalone | This parameter specifies whether to enable the feature that allows a tenant's GTS service to exclusively use a set of units. |
| balancer_idle_time | Sets the wake-up interval for idle threads of background tasks such as load balancing. |
| enable_rebalance | It specifies whether to enable automatic load balancing. |
| enable_transfer | Controls whether data transfer is allowed within a tenant. If this parameter is disabled, data transfer is not allowed.enable_rebalanceThis parameter is invalid. |
| partition_balance_schedule_interval | The partition balancing scheduling cycle. |
| enable_database_sharding_none | Controls whether to enable automatic aggregation for user tables when creating a database. |
Replica-related
Parameter name |
Feature description |
|---|---|
| replica_parallel_migration_mode | Specifies the mode for the parallel migration of log stream replicas. |
| choose_migration_source_policy | Specifies the priority strategy for selecting source replicas during migration. |
Scaling-related
Parameter name |
Feature description |
|---|---|
| ls_scale_out_factor | The scaling factor of log streams, which controls the number of log streams for a tenant on each service node. |
Backup and recovery-related
Parameter name |
Feature description |
|---|---|
| recover_table_concurrency | Specifies the maximum number of tables that can be restored in parallel during the cross-tenant table import phase of table-level restore. |
| recover_table_dop | Specifies the maximum number of tables that can be restored in parallel during the cross-tenant table import phase of table-level restore. |
| log_restore_concurrency | Sets the concurrency level 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. |
Partitioning-related
Parameter name |
Feature description |
|---|---|
| enable_auto_split | Controls whether to enable automatic partitioning for the tenant. |
| auto_split_tablet_size | It specifies the threshold for triggering a split after the auto-partitioning feature is enabled for this tenant. |
| global_index_auto_split_policy | Specifies whether to enable automatic partitioning for the newly created global index. Default value:DISTRIBUTED. |
Background execution thread-related
Parameter name |
Feature description |
|---|---|
| px_workers_per_cpu_quota | Sets the proportion of worker threads for parallel execution. |
| ddl_thread_score | Specifies the number of threads used by the DDL task. |
| compaction_low_thread_score | Sets 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 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_queueNumber of threads. The default value of 0 indicates to take all available threads.unit_min_cpuThe value of . |
| tenant_sql_net_thread_count | This parameter specifies the number of I/O threads for a MySQL-compatible tenant.sql_nio_serverNumber of threads. The default value of 0 indicates to take all available threads.unit_min_cpuThe value of . |
| ddl_high_thread_score | This parameter is used to modify the number of DAG threads for executing DDL KV merge. |
Caching-related
Parameter name |
Feature description |
|---|---|
| enable_adaptive_plan_cache | This parameter specifies whether to enable adaptive plan cache for the tenant. |
| result_cache_max_size | Used to controlresult cacheThe maximum memory size that the module can use. |
| result_cache_max_result | Used to control a singleresult cacheThe maximum number of cache objects that can be used isresult_cache_max_sizeThe memory usage of the process. |
| ob_result_cache_evict_percentage | Used to setresult cacheMemory eviction watermark. |
| ob_deterministic_udf_cache_max_size | Used to mark the statement execution period. AlldeterministicThe maximum total memory that can be used by the cache pool of the UDF. |
I/O-related
Parameter name |
Feature description |
|---|---|
| io_category_config | It specifies the percentage of I/O requests for each category. |
Compatibility
Note
The parameters in the following table currently take effect only in MySQL-compatible mode.
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. |
Routing
Parameter name |
Feature description |
|---|---|
| ob_proxy_readonly_transaction_routing_policy | Controls whether the proxy's routing for transactions is affected by read-only statements. |
LOB Data
Parameter name |
Feature description |
|---|---|
| lob_enable_block_cache_threshold | Sets the threshold for caching LOB queries stored in OUTROW format. |
Memory space
Parameter name |
Feature description |
|---|---|
| ob_vector_memory_limit_percentage | Configures the memory usage threshold for the vector index module, in percentage. |
| range_optimizer_max_mem_size | The memory used by the Query Range module. |
| rpc_memory_limit_percentage | Sets the maximum memory for RPCs in a tenant as a percentage of the tenant's total memory. |
| query_memory_limit_percentage | Specifies the percentage of tenant memory available for a single SQL statement. |
Disk Space
Parameter name |
Feature description |
|---|---|
| temporary_file_max_disk_size | Sets the maximum disk space that temporary files on a single node of a tenant can occupy. |
OBKV-related
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 errors. |
| kv_ttl_duty_duration | Set the daily scheduled trigger period for the TTL task. The TTL task is triggered once within this period. |
| kv_group_commit_batch_size | Specifies the size of the batch operations executed during an OBKV group commit. |
| kv_group_commit_rw_mode | Used to control scenarios where group commits are performed. |
| kv_hbase_client_scanner_timeout_period | Sets the timeout period for OBKV-HBase streaming queries. |
| kv_ttl_history_recycle_interval | Specifies the retention period for historical task records. |
| ttl_thread_score | Specifies the number of worker threads used by the TTL task. |
| kv_ttl_delete_max_ops | Specifies the maximum number of operations for which a task can be deleted based on the TTL. |
PL-related
Parameter name |
Feature description |
|---|---|
| plsql_code_type | Specifies the compilation type for PL/SQL code. |
| plsql_debug | Specifies whether to compile the library into a debug version. |
| plsql_optimize_level | Specifies the compilation optimization level. |
| plsql_v2_compatibility | Specifies the compatibility features for Oracle 8. |
| package_state_sync_max_size | Used to control the serializable length for a single package state. |
| ob_enable_java_udf | This parameter specifies whether to enable or disable Java UDF. |
| enable_pl_rich_error_msg | This parameter specifies whether to enable or disable the feature of appending additional information to exception messages when they are thrown in PL/SQL. |
Direct load related
Parameter name |
Feature description |
|---|---|
| default_load_mode | It is used to control the data import method in data import scenarios. |
| direct_load_allow_fallback | This parameter specifies whether to roll back the data import operation to a normal import method if a scenario not supported by direct load is encountered during the specified data import operation. |
| load_data_diagnosis_log_compression | Sets the compression algorithm used for diagnostic logs. |
| load_data_diagnosis_log_max_size | Sets the size of a single diagnostic log file. |
PX-related
Parameter name |
Feature description |
|---|---|
| px_target_high_watermark | The high-watermark percentage threshold for controlling the number of parallel threads. |
| px_target_low_watermark | The low-watermark percentage threshold for setting the number of parallel threads. |
| px_target_workers_per_cpu | It is used to control the expected ratio of parallel execution threads to the number of tenant CPUs. |
Others
Parameter name |
Feature description |
|---|---|
| zone_deploy_mode | Sets the distribution pattern of tenants across zones. |
| enable_early_lock_release | This parameter specifies whether to enable the pre-row unlocking 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.subjectin thecnField (common name). |
| ob_enable_batched_multi_statement | It specifies 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, aiming to control task competition for tenant resources. |
| default_auto_increment_mode | Sets the default auto-increment mode for auto-increment columns. |
| ob_query_switch_leader_retry_timeout | Specifies 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 | Controls the cycle for persisting tenant data dictionaries. |
| enable_user_defined_rewrite_rules | A switch for controlling whether user-defined rules are enabled. |
| storage_rowsets_size | Controls the number of rows processed in a vectorized batch by the columnar storage engine. |
| approx_count_distinct_precision | Used to configureapprox_count_distinctThe precision of the function result. |
| default_skip_index_level | Used to specify when to create tables in a tenant.skip_index_levelThe default value of . |
| sql_func_extension_mode | This function is used to control whether to enable the mainstream compatibility mode that uses a naming style inconsistent with MySQL. |
| enable_ps_parameterize | It is used to control whether to parameterize the PS statement during parsing. |
Transactions and transaction logs
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 tenant log disk space multiplied by this value, log writing is no longer allowed. |
| log_disk_utilization_threshold | Sets the threshold for tenant log disk usage. When a tenant's log disk usage exceeds the total log disk space of the tenant multiplied by this value, log file reuse is triggered. |
| 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 | It specifies the percentage threshold of the MemStore memory usage relative to the total MemStore memory that triggers a write throttling. |
| standby_db_fetch_log_rpc_timeout | Sets the RPC timeout period for log pulling from the standby database. This controls how long the standby database's log transfer service waits before detecting that a primary server is unavailable and switching to another server. |
| 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 in the transaction module. |
| clog_persistence_compress_func | Specifies the compression algorithm for persisting transaction logs to disk. |
| enable_clog_persistence_compress | Specifies whether to enable compression for transaction log persistence on disk. |
Data types
Parameter name |
Feature description |
|---|---|
| json_document_max_depth | Specifies the maximum number of nested levels allowed in a JSON document. |
Lock-related
Parameter name |
Feature description |
|---|---|
| enable_lock_priority | Table lock priority switch. |
External tables
Parameter name |
Feature description |
|---|---|
| external_table_io_hole_size | Sets the maximum distance (in bytes) between two consecutive I/O ranges. |
| external_table_io_range_size | Specifies the maximum size of the major compaction range in bytes. |
System logs
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 is 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 delay before tenant log archiving starts. |
Materialized views
Parameter name |
Feature description |
|---|---|
| enable_mlog_auto_maintenance | Controls whether to enable automatic materialized view log management. |
| mlog_trim_interval | It is used to control the scheduling cycle of the automatic mlog pruning task in the background. |
| enable_mv_binlog_minimal_mode | Used to control the incremental refresh scenario of materialized views.binlog minimalThe switch for the mode. |
User login
Note
The parameters in the following table currently take effect only in MySQL-compatible mode.
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. |
Compression algorithms
Parameter name |
Feature description |
|---|---|
| spill_compression_codec | Specifies the compression algorithm type for implementing data compression during SQL execution. |
| ob_encoding_granularity | Sets the maximum number of rows for encoding a single microblock. |
Minor compaction and major compaction related
Parameter name |
Feature description |
|---|---|
| enable_window_compaction | Specifies whether to use window merging for the current tenant. |
| mds_minor_compact_trigger | Controls the number of SSTables that trigger a minor compaction for MDS. |
| mds_compaction_mid_thread_score | This parameter specifies the number of DAG threads for medium-priority MDS compaction. |
| mds_compaction_high_thread_score | Sets the number of DAG (direct acyclic graph) threads for high-priority MDS compaction. |
| default_progressive_merge_num | Specifies the default number of progressive major compactions for a newly created table. |
| major_freeze_duty_time | Specifies the trigger time for daily scheduled freezing and major compaction. |
| major_compact_trigger | Specifies the number of major compactions triggered by freezes. |
| minor_compact_trigger | Configures the threshold for the number of SSTables that triggers a minor compaction. |
| undo_retention | Specifies the duration for which the system retains multi-version data, in seconds. This setting controls the recycling of multi-version data during minor compactions. |
| 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 | Sets the number of threads for daily major compaction. |
| merger_completion_percentage | This parameter specifies the percentage threshold for the number of replicas completed with major compactions. When this threshold is reached, the scheduling for the current round of major compactions is considered complete. |
| merger_switch_leader_duration_time | 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. |
Arbitration service
Parameter name |
Feature description |
|---|---|
| arbitration_timeout | Sets the timeout period for triggering automatic downgrade. |
TTL related
Parameter name |
Feature description |
|---|---|
| enable_ttl | Controls whether to enable the TTL feature in SQL mode. |
| ttl_duty_time | Specifies the time point at which the backend periodically triggers the execution of the TTL task. |
AI Function Service
Parameter name |
Feature description |
|---|---|
| document_ai_file_max_size | Used to limitLOAD_FILEThe maximum file size that can be processed by the function at one time. |
Unsupported parameters
Parameter name |
Feature description |
|---|---|
| sql_work_area | Sets the workspace memory for a tenant. |
| max_stale_time_for_weak_consistency | Specifies how old data is allowed to be read during weak-consistency reads. |
