This topic describes the cluster-level and tenant-level parameters of OceanBase Database based on their functions.
Cluster-level parameters
Security
| Parameter | Description |
|---|---|
| mysql_port | The port number for the SQL service protocol. |
| rpc_port | The port number for the remote access protocol. |
| sql_protocol_min_tls_version | The minimum SSL/TLS protocol version for SSL connections to the database. |
| ssl_client_authentication | Whether to enable the SSL connection feature. |
| ssl_external_kms_info | The information required for the SSL feature of OceanBase Database. This parameter records the configurations required for different SSL usage modes in a JSON string. The JSON string must contain the ssl_mode field. |
| enable_sql_audit | Whether to enable the SQL audit feature. |
Backup and restore
| Parameter | Description |
|---|---|
| backup_backup_dest | The destination for backing up backup data. |
| backup_backup_dest_option | The parameters for backup backup. |
| backup_dest_option | The parameters for backup. |
| backup_concurrency | The number of concurrent writes to the file system during backup. |
| backup_dest | The path for baseline backup and log archiving. |
| backup_log_archive_option | The options for archiving backup logs. |
| backup_net_limit | The total bandwidth for cluster backup. |
| backup_recovery_window | The time window for restoring backup data. |
| backup_region | The region for executing backup. |
| backup_zone | The zone for executing backup. |
| log_archive_batch_buffer_limit | The maximum memory usage for log archiving on a single node. |
| log_archive_checkpoint_interval | The time interval for cold data log archiving checkpoints. |
| restore_concurrency | The maximum concurrency for restoring tenant data from a backup. |
| ob_storage_s3_url_encode_type | Whether to enable URL encoding that is compatible with the RFC 3986 standard when sending requests to S3. |
Cgroup
| Parameter | Description |
|---|---|
| enable_cgroup | Whether to enable the Cgroup feature on the OBServer node. |
CPU-related
| Parameter | Description |
|---|---|
| cpu_count | Specifies the total number of CPU cores. If you set this parameter to 0, the system automatically detects the number of CPU cores. |
| server_balance_cpu_mem_tolerance_percent | Specifies the tolerance for CPU and memory resource imbalance in the node load balancing strategy. |
| server_cpu_quota_max | Specifies the maximum CPU quota that can be used by the system. |
| server_cpu_quota_min | Specifies the minimum CPU quota that can be used by the system. The system automatically reserves this quota. |
| token_reserved_percentage | Specifies the percentage of idle tokens reserved for each tenant in CPU scheduling. |
| workers_per_cpu_quota | Specifies the number of worker threads allocated to each CPU quota. |
| cpu_reserved | Specifies the number of CPU cores reserved for the system. The remaining CPU cores are exclusively used by OceanBase Database. |
| sys_cpu_limit_trigger | Specifies the CPU utilization threshold. When the CPU utilization exceeds this threshold, the execution of system background tasks is paused. |
| system_cpu_quota | Specifies the CPU quota available to the system tenant. |
| tenant_cpu_variation_per_server | Specifies the allowed deviation in CPU quota scheduling among multiple units of a tenant. |
DBLink-related
| Parameter | Description |
|---|---|
| enable_dblink | Specifies whether to enable the DBLink feature. |
Read/write/query-related
| Parameter | Description |
|---|---|
| weak_read_version_refresh_interval | Specifies the refresh cycle for weak-consistency read versions, which affects the latency of weak-consistency read data. |
| large_query_worker_percentage | Specifies the percentage of worker threads reserved for processing large queries. |
| large_query_threshold | Specifies the query execution time threshold. |
| trace_log_slow_query_watermark | Specifies the query execution time threshold. If the execution time of a query exceeds this threshold, it is considered a slow query, and the trace logs of slow queries are printed to the system log. |
Partition-related parameters
| Parameter name | Description |
|---|---|
| tablet_meta_table_check_interval | Specifies the interval at which the background thread of the DBA_OB_TABLET_REPLICAS/CDB_OB_TABLET_REPLICAS view checks for changes. |
| tablet_meta_table_scan_batch_count | Specifies the number of tablets cached in memory by the tablet meta table iterator. |
| tablet_size | Specifies the size of each tablet during parallel processing (such as major compactions and queries) within a partition. |
| auto_broadcast_location_cache_rate_limit | Specifies the maximum number of partitions whose location information can be broadcasted per second by each OBServer node. |
| auto_refresh_location_cache_rate_limit | Specifies the maximum number of partitions that can be automatically refreshed per second by each OBServer node. |
| enable_pg | Specifies whether to enable the partition group feature. |
| gc_wait_archive | Specifies whether to wait for all logs of a partition to be archived before performing partition garbage collection. |
| partition_table_check_interval | Specifies the interval at which an OBServer node deletes non-existent replicas from a partition table. |
Load balancing
| Parameter | Description |
|---|---|
| balancer_log_interval | Specifies the interval at which the statistics logs of the disaster recovery task thread are printed. |
| balancer_task_timeout | Specifies the timeout period for background tasks such as load balancing. |
| balancer_tolerance_percentage | Specifies the tolerance for disk imbalance among multiple units of a tenant in the load balancing strategy. If the imbalance is within the mean value plus or minus the tolerance, no load balancing action is triggered. |
| server_balance_critical_disk_waterlevel | Specifies the water level for the disk load balancing feature. |
| server_balance_disk_tolerance_percent | Specifies the tolerance for disk load imbalance in the node-to-node disk load balancing strategy. |
| resource_hard_limit | Specifies the over-subscription percentage of CPU resources. |
| enable_sys_unit_standalone | Specifies whether to enable the standalone mode for the system tenant. |
| balancer_emergency_percentage | Specifies the unit load threshold. If the unit load exceeds this threshold, the system allows replica migration even during major compactions. |
| balancer_timeout_check_interval | Specifies the interval at which the timeout period for background tasks such as load balancing is checked. |
| data_copy_concurrency | Specifies the maximum number of concurrent data migration and replication tasks that can be executed in the system. |
| tenant_groups | Specifies the tenant groups used in the load balancing strategy. |
| unit_balance_resource_weight | Specifies the resource weights used in the unit load balancing strategy. This parameter is not usually manually configured. |
| resource_soft_limit | Specifies whether to enable unit load balancing. |
| unit_gc_wait_time | Specifies the maximum wait time for unit garbage collection (GC). If the wait time exceeds the maximum, the system forces GC. |
Replica-related parameters
| Parameter | Description |
|---|---|
| enable_rereplication | Enables or disables automatic migration and replication of log stream replicas. |
| ls_meta_table_check_interval | Specifies the interval at which the background thread checks the DBA_OB_LS_LOCATIONS and CDB_OB_LS_LOCATIONS views. |
| sys_bkgd_migration_change_member_list_timeout | Specifies the timeout for changing the Paxos member group during replica migration. |
| sys_bkgd_migration_retry_num | Specifies the maximum number of retries for replica migration failures. |
| balance_blacklist_failure_threshold | Specifies the threshold for the number of consecutive failures of background tasks such as replica migration. If the number of consecutive failures exceeds the threshold, the tasks are added to 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 | Specifies the CPU quota allocated to background tasks related to replica election. |
| election_blacklist_interval | Specifies the interval during which a failed leader cannot be selected again. |
| enable_auto_leader_switch | Enables or disables automatic leader switching. |
| enable_smooth_leader_switch | Enables or disables smooth leader switching. |
| global_index_build_single_replica_timeout | Specifies the timeout for building a global index on each replica. |
| get_leader_candidate_rpc_timeout | Specifies the timeout for internal requests to obtain leader candidates in automatic leader switching. |
| migrate_concurrency | Specifies the maximum number of concurrent internal data migrations. |
| rebuild_replica_data_lag_threshold | Specifies the threshold for the gap between the transaction logs of the standby replica and the leader. If the gap exceeds the threshold, the replica is rebuilt. |
| 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 safe retention period for deleted replicas. |
Cache-related parameters
| Parameter | Description |
|---|---|
| bf_cache_miss_count_threshold | Specifies the number of macroblock misses that triggers the creation of a Bloom filter cache. |
| bf_cache_priority | Specifies the priority of the Bloom filter cache. |
| cache_wash_threshold | Specifies the capacity threshold that triggers cache cleaning. |
| fuse_row_cache_priority | Specifies the priority of the fused row cache in the cache system. |
| user_row_cache_priority | Specifies the priority of the baseline data row cache in the cache system. |
| autoinc_cache_refresh_interval | Specifies the refresh interval of the auto-increment column cache. |
| plan_cache_evict_interval | Specifies the eviction interval of the execution plan cache. |
| index_block_cache_priority | Specifies the priority of the metadata index microblock cache. |
| opt_tab_stat_cache_priority | Specifies the priority of the statistics cache. |
| tablet_ls_cache_priority | Specifies the priority of the tablet mapping cache. |
| user_block_cache_priority | Specifies the priority of the data block cache in the cache system. |
| index_info_block_cache_priority | Specifies the priority of the block index in the cache system. |
| index_cache_priority | Specifies the priority of the index in the cache system. |
| user_tab_col_stat_cache_priority | Specifies the priority of the statistics cache in the cache system. |
| plan_cache_high_watermark | Specifies the memory usage threshold of the execution plan cache. If this threshold is exceeded, the cache is automatically evicted. |
| plan_cache_low_watermark | Specifies the memory usage threshold of the execution plan cache. If this threshold is exceeded, the cache is automatically evicted. |
| dtl_buffer_size | Specifies the size of the cache used by the SQL data transfer module. |
Background execution threads
| Parameter | Description |
|---|---|
| sql_net_thread_count | The number of MySQL cluster I/O threads, that is, the number of global_sql_nio_server threads. The default value of 0 indicates the same value as the net_thread_count parameter. |
| auto_leader_switch_interval | The interval between automatic leader switching background threads. |
| switchover_process_thread_count | The size of the thread pool for primary-standby database switching. |
I/O
| Parameter | Description |
|---|---|
| syslog_io_bandwidth_limit | The maximum disk I/O bandwidth that system logs can occupy. System logs exceeding this bandwidth will be discarded. |
| disk_io_thread_count | The number of disk I/O threads. It must be an even number. |
| net_thread_count | The number of network I/O threads. |
| high_priority_net_thread_count | The number of high-priority network threads. |
| data_storage_error_tolerance_time | The maximum time that the system tolerates when the data disk is in the ERROR state. |
| sys_bkgd_io_high_percentage | The maximum percentage of system background I/O. |
| sys_bkgd_io_low_percentage | The minimum percentage of system background I/O. |
| user_iort_up_percentage | The threshold for user disk I/O latency. If the user disk I/O latency exceeds this threshold, the system will limit the background I/O tasks. |
| ob_esi_rpc_port | The communication port between the obesi process and the observer process. |
| enable_ob_esi_process | Specifies whether to enable the obesi (external storage interface) process. |
| ob_esi_session_timeout | The timeout period for active session resources held by the obesi process. |
| ob_esi_io_concurrency | The number of concurrent I/O operations for the obesi process. |
| ob_esi_syslog_level | The current log recording level for the obesi process. |
| ob_esi_max_syslog_file_count | The maximum number of log files that the obesi process can hold before recycling them. |
| multiblock_read_gap_size | The maximum capacity of a single I/O aggregation read block cache. |
| multiblock_read_size | The size of I/O aggregation during data reading. |
Cluster-related
| Parameter name | Description |
|---|---|
| all_server_list | Displays the addresses of all servers in the cluster. |
| cluster | Specifies the name of the OceanBase cluster. |
| cluster_id | Specifies the ID of the OceanBase cluster. |
| rpc_timeout | Specifies the timeout period for internal cluster requests. |
| all_cluster_list | Displays the list of servers that access the same config_url. |
| enable_election_group | Specifies whether to enable the election group strategy. |
| obconfig_url | Specifies the URL address of the OBConfig service. |
| local_ip | Specifies the IP address of the server on which the ObServer is installed. |
| observer_id | Specifies the unique identifier assigned to the OBServer node by the RS in the cluster. |
| min_observer_version | Specifies the minimum application version of the OBServer nodes in the cluster. |
| zone | Specifies the name of the zone where the node is located. |
Bandwidth-related
| Parameter name | Description |
|---|---|
| enable_ob_ratelimit | Specifies whether to enable rate limiting for cross-region RPC connections. |
| ob_ratelimit_stat_period | Specifies the time interval for the OBServer node to calculate and update the maximum bandwidth. |
| sys_bkgd_net_percentage | Specifies the percentage of network bandwidth that can be occupied by background system tasks. |
| devname | Displays the name of the network interface card (NIC) device bound to the service process. |
Location cache
| Parameter name | Description |
|---|---|
| virtual_table_location_cache_expire_time | Specifies the cache expiration time of the location information of a virtual table. |
| location_cache_refresh_rpc_timeout | Specifies the timeout period for an RPC call to refresh the location_cache. |
| location_cache_refresh_sql_timeout | Specifies the timeout period for an SQL statement to refresh the location_cache. |
| location_cache_refresh_min_interval | Specifies the minimum interval for location cache refresh requests to prevent excessive refresh requests from causing excessive system pressure. |
| location_cache_cpu_quota | Specifies the CPU quota for the location cache module. |
| location_fetch_concurrency | Specifies the maximum number of concurrent location cache refresh requests for a single server. |
| location_refresh_thread_count | Specifies the number of threads for OBServer nodes to obtain partition location information from the Root Service. |
| enable_auto_refresh_location_cache | Specifies whether to enable the automatic refresh of location cache information. |
Directory path
| Parameter name | Description |
|---|---|
| config_additional_dir | Specifies multiple directories for storing configuration files to provide redundancy. |
| data_dir | Specifies the directory for storing data such as SSTables. |
Memory-related
| Parameter | Description |
|---|---|
| datafile_disk_percentage | The percentage of the total space of the disk where the data_dir directory is located (the disk where the data_dir directory is located will be initialized by the OceanBase Database system for data storage). |
| data_disk_usage_limit_percentage | The maximum percentage of space that can be written to data files. If this threshold is exceeded, data migration is prohibited. |
| enable_sql_operator_dump | Specifies whether to allow intermediate results of SQL processing to be written to disk to release memory. |
| global_write_halt_residual_memory | The global residual memory threshold that triggers a pause in write operations for normal tenants (write operations for the sys tenant are not affected). |
| leak_mod_to_check | Specifies the name of the module to check for memory leaks. This is an internal debugging feature. |
| memory_chunk_cache_size | The size of memory blocks cached by the memory allocator. |
| memory_limit | The total available memory size. |
| memory_limit_percentage | The percentage of the total available memory size relative to the total memory size. |
| memory_reserved | The size of memory reserved for the underlying modules of the system. |
| memstore_limit_percentage | The percentage of memory used by MemStore relative to the total available memory for the tenant. |
| system_memory | The size of memory reserved for the tenant with tenant ID 500. |
| use_large_pages | Manages the use of large pages for database memory. |
| datafile_maxsize | The maximum size to which disk files can automatically expand. |
| datafile_next | The increment size for disk file auto-expansion. |
| storage_meta_cache_priority | Controls the priority of storage Meta Cache in the kvcache. |
| stack_size | The size of the program function call stack. |
| enable_asan_for_memory_context | Specifies whether to use ObAsanAllocator as the MemoryContext allocator when ob_asan is enabled (default is ObAllocator). |
PX-related parameters
| Parameter name | Description |
|---|---|
| px_workers_per_cpu_quota | Specifies the ratio of parallel execution worker threads. |
| px_task_size | Specifies the amount of data processed by each task of the SQL parallel query engine. |
| max_px_worker_count | Specifies the maximum number of threads used by the SQL parallel query engine. |
Other parameters
| Parameter name | Description |
|---|---|
| bf_cache_miss_count_threshold | Specifies the number of macroblock misses that trigger the creation of a Bloomfilter cache. |
| bf_cache_priority | Specifies the priority of the Bloom Filter cache. |
| cache_wash_threshold | Specifies the capacity threshold that triggers cache cleaning. |
| fuse_row_cache_priority | Specifies the priority of the fused row cache in the cache system. |
| autoinc_cache_refresh_interval | Specifies the refresh interval of the auto-increment column cache. |
| index_block_cache_priority | Specifies the priority of the metadata index microblock cache. |
| tablet_ls_cache_priority | Specifies the priority of the tablet mapping cache. |
| user_block_cache_priority | Specifies the priority of the data block cache in the cache system. |
| enable_perf_event | Specifies whether to enable the collection of performance event information. |
| recyclebin_object_expire_time | Specifies the time after which schema objects in the recycle bin are automatically cleaned up. |
| schema_history_expire_time | Specifies the range of complete metadata history data to be retained, and can also be used to set the retention time for tenants to be deleted. |
| schema_history_recycle_interval | Specifies the interval at which the system executes the schema multiversion record recycling task. |
Log-related
| Parameter name | 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 | Specifies whether to enable the option to record logs before the OBServer node starts. This parameter, together with max_syslog_file_count, determines whether the recycling logic considers old log files. |
| enable_syslog_wf | Specifies whether to print system logs at the WARN level or higher to a separate log file. |
| max_string_print_length | Specifies the maximum length of a single line of system logs. |
| max_syslog_file_count | Specifies the maximum number of log files that can be retained before recycling. |
| syslog_level | Specifies the system log level. |
| trace_log_sampling_interval | Specifies the interval at which trace log information is printed periodically. |
| diag_syslog_per_error_limit | Specifies the maximum number of DIAG system logs allowed per second for each error code. Logs exceeding this threshold will not be printed. |
| alert_log_level | Specifies the alert log level. |
| log_storage_warning_trigger_percentage | Specifies the write performance percentage threshold that triggers a log disk failure warning. |
Root Service related
| Parameter name | Description |
|---|---|
| rootservice_async_task_queue_size | Specifies the size of the internal asynchronous task queue of the Root Service. |
| rootservice_async_task_thread_count | Specifies the size of the internal asynchronous task thread pool of the Root Service. |
| rootservice_list | Displays the list of machines where the Root Service and its replicas are located. |
| rootservice_ready_check_interval | Specifies the interval at which the Root Service waits for and checks the cluster status after it is started. |
| rootservice_memory_limit | Specifies the maximum memory capacity limit of the Root Service. |
| lease_time | Specifies the heartbeat lease period. |
| server_check_interval | Specifies the interval at which the server table consistency is checked. |
| server_permanent_offline_time | Specifies the threshold for node heartbeat interruption. After the heartbeat is interrupted for this period, the node is considered permanently offline. Data replicas on permanently offline nodes need to be automatically replenished. |
| ob_event_history_recycle_interval | Controls the interval for recycling historical events. |
| enable_rootservice_standalone | Specifies whether to allow the system tenant and RootService to exclusively use the OBServer node. |
| fast_recovery_concurrency | Controls the number of concurrent fast recovery tasks scheduled by the RootService on the OBServer. |
| wait_leader_batch_count | Specifies the maximum number of partitions per batch for the RootService to send a leader switch command. |
RPC authentication
| Parameter name | Description |
|---|---|
| rpc_client_authentication_method | Specifies the security authentication method for the RPC client. |
| rpc_server_authentication_method | Specifies the security authentication method for the RPC server. |
Data migration
| Parameter name | Description |
|---|---|
| migration_disable_time | Controls the cooldown period during which new data migration operations are prohibited after a data migration fails due to resource exceptions, such as disk space exhaustion. |
SQL-related
| Parameter name | Description |
|---|---|
| sql_login_thread_count | The number of threads for handling SQL login requests. |
| sql_audit_memory_limit | The maximum memory that can be occupied by SQL audit data. |
| enable_sys_table_ddl | Specifies whether to allow manual creation of system tables. |
| internal_sql_execute_timeout | The time interval for system internal DML requests. |
| enable_ddl | Specifies whether to allow execution of DDL. |
Transaction and transaction log related
| Parameter | Description |
|---|---|
| log_disk_size | Specifies the size of the redo log disk. |
| log_disk_percentage | Specifies the percentage of the total space occupied by the redo logs on the disk. |
| ignore_replay_checksum_error | Specifies whether to ignore checksum errors during transaction log replay. |
| trx_2pc_retry_interval | Specifies the interval between automatic retries for two-phase commit failures. |
| standby_fetch_log_bandwidth_limit | Specifies the maximum bandwidth that can be occupied by the total amount of log synchronization traffic from all servers in the standby tenant cluster to the primary tenant. |
| log_storage_warning_tolerance_time | Specifies the time from when a disk I/O failure occurs on the log disk to when the disk is marked as a bad disk. |
| clog_disk_utilization_threshold | Specifies the watermark for reusing the space of the clog or ilog disk. |
| clog_expire_days | Specifies the expiration time of the clog file. When the last modification time of the clog file exceeds the expiration time, the file is deleted. |
| clog_cache_priority | Specifies the priority of the cache space occupied by the transaction log. |
| clog_disk_usage_limit_percentage | Specifies the maximum percentage of the available disk space for the transaction log. |
| clog_sync_time_warn_threshold | Specifies the threshold for the transaction log synchronization time. A warning log is generated when the synchronization time exceeds this threshold. |
| clog_transport_compress_func | Specifies the compression algorithm used for internal transaction log transmission. |
| enable_one_phase_commit | Specifies whether to enable the one-phase commit optimization feature. |
| enable_separate_sys_clog | Specifies whether to store system transaction logs separately from user transaction logs. |
| flush_log_at_trx_commit | Specifies the write strategy for transaction logs during transaction commit. |
| index_clog_cache_priority | Specifies the priority of transaction log indexes in the cache system. |
| ilog_index_expire_time | Specifies the maximum time for which an OBServer can provide Ilog files for reading. |
| trx_force_kill_threshold | Specifies the maximum waiting time for killing a transaction when it is frozen or needs to be killed. |
Lock related
| Parameter | Description |
|---|---|
| trx_try_wait_lock_timeout | Specifies the wait time for row locks during statement execution. |
Debugging-related parameters
| Parameter name | Description |
|---|---|
| debug_sync_timeout | Enables the Debug Sync feature and sets the timeout period. |
| enable_rich_error_msg | Specifies whether to add debugging information such as the server address, time, and trace ID to the client message. |
TCP-related parameters
| Parameter name | Description |
|---|---|
| enable_tcp_keepalive | Enables or disables the keepalive mechanism for client connections. |
| tcp_keepidle | Specifies the time in seconds after which a keepalive probe is sent if no data is transmitted after a client connects to a server. |
| tcp_keepintvl | Specifies the time interval in seconds between two consecutive keepalive probes. |
| tcp_keepcnt | Specifies the maximum number of retries before closing an inactive connection. |
System log-related
| Parameter | 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 | Specifies whether to enable the recording of logs generated before the OBServer node starts. This parameter, together with max_syslog_file_count, determines whether the recycling logic considers old log files. |
| enable_syslog_wf | Specifies whether to print system logs of WARN level and above to a separate log file. |
| max_string_print_length | Specifies the maximum length of a single line of system log. |
| max_syslog_file_count | Specifies the maximum number of log files that can be retained before recycling. |
| syslog_level | Specifies the system log level. |
| trace_log_sampling_interval | Specifies the interval at which trace logs are periodically printed. |
| diag_syslog_per_error_limit | Specifies the maximum number of DIAG system logs allowed per second per error code. Logs exceeding this threshold will not be printed. |
| enable_log_archive | Specifies whether to enable log archiving. |
| system_trace_level | Specifies the log printing level for system trace logs. |
| enable_record_trace_log | Specifies whether to record trace logs. |
| enable_syslog_recycle | Specifies whether to enable the recording of logs generated before the OBServer node starts. This parameter, together with max_syslog_file_count, determines whether the recycling logic considers old log files. |
| enable_syslog_wf | Specifies whether to print system logs of WARN level and above to a separate log file. |
| max_string_print_length | Specifies the maximum length of a single line of system log. |
| max_syslog_file_count | Specifies the maximum number of log files that can be retained before recycling. |
| trace_log_sampling_interval | Specifies the interval at which trace logs are periodically printed. |
| diag_syslog_per_error_limit | Specifies the maximum number of DIAG system logs allowed per second per error code. Logs exceeding this threshold will not be printed. |
| alert_log_level | Specifies the alert log level. |
| log_storage_warning_trigger_percentage | The write performance percentage threshold that triggers a log disk fault. |
Compression algorithms
| Parameter | Description |
|---|---|
| default_compress_func | Specifies the default compression algorithm for table data. You can also specify a different compression algorithm when you create a table. |
| default_compress | Specifies the default compression strategy for tables created in Oracle mode. |
| default_transport_compress_func | Specifies the RPC compression algorithm for the entire cluster. |
Dump and major compaction
| Parameter | Description |
|---|---|
| enable_major_freeze | Specifies whether to enable automatic global freezing. |
| micro_block_merge_verify_level | Specifies the verification level for macroblocks during compaction. |
| row_compaction_update_limit | Specifies the number of modifications that trigger in-memory row data compaction. |
| enable_global_freeze_trigger | Specifies whether to enable automatic global freezing. |
| enable_merge_by_turn | Specifies whether to enable the round-robin compaction strategy. |
| enable_manual_merge | Specifies whether to enable manual compaction. |
| global_major_freeze_residual_memory | Specifies the residual memory threshold for triggering global freezing. That is, global freezing is triggered when the residual memory is less than this percentage. |
| minor_deferred_gc_time | Specifies the interval between the end of a compaction and the start of the garbage collection of the resulting SSTables. |
| zone_merge_concurrency | Specifies the number of zones that can be compacted concurrently. If the value is 0, the system automatically selects the optimal concurrency level based on the deployment. |
| zone_merge_order | Specifies the order of zone compaction. If not specified, the system automatically determines the order. |
| zone_merge_timeout | Specifies the timeout period for a single zone's compaction. |
| minor_freeze_times | Specifies the number of minor freezes that trigger a major compaction. |
| minor_merge_concurrency | Specifies the number of threads for concurrent compaction. |
| minor_warm_up_duration_time | Specifies the preheating time for generating new minor SSTables. |
| row_purge_thread_count | Specifies the maximum number of threads for in-memory row data compaction. |
Arbitration service
| Parameter | Description |
|---|---|
| arbitration_degradation_policy | Specifies the automatic degradation strategy. |
| ob_startup_mode | Specifies the startup mode for an OBServer node. This parameter can be modified only during the first startup. |
Resource isolation
| Parameter | Description |
|---|---|
| enable_global_background_resource_isolation | Enables global foreground and background resource isolation. |
| global_background_cpu_quota | Specifies the CPU quota for background tasks when global foreground and background resource isolation is enabled. |
Tenant-level parameters
Security-related
| Parameter | Description |
|---|---|
| external_kms_info | The storage key management information. |
| tde_method | The transparent tablespace encryption method. |
| audit_sys_operations | Specifies whether to trace system user operations. |
| audit_trail | Specifies whether to enable database auditing. |
| audit_log_buffer_size | Specifies the size of the buffer for asynchronous log writes. |
| audit_log_compression | This parameter specifies the compression algorithm used for audit logs. |
| audit_log_enable | This parameter specifies whether to enable the audit feature. |
| audit_log_format | Configures the file format of the audit log. |
| audit_log_max_size | The maximum amount of audit logs stored on a single OBServer node. |
| audit_log_path | The directory where you can store the audit logs. |
| audit_log_prune_seconds | Controls the maximum retention period of an audit log. |
| audit_log_query_sql | Controls how SQL statements are recorded in audit logs. |
| audit_log_rotate_on_size | The maximum size of an individual audit log file. |
| audit_log_strategy | Determines the audit log file writing strategy. |
| sts_credential | Specifies the access credential used for accessing the STS service of OCP. |
| ob_ssl_invited_common_names | This attribute stores the list of application identities of the current tenant. The identities are extracted from the cn field of the subject attribute in the client certificate used in mutual TLS authentication. |
CPU-related configurations
| Parameter name | Description |
|---|---|
| cpu_quota_concurrency | The maximum number of concurrent sessions allowed for each CPU quota of the tenant. |
Read/write and query-related
| Parameter | 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 refresh the information_schema.QUERY_RESPONSE_TIME view and read query_response_time_range_base again. |
| query_response_time_range_base | Specifies the time interval base for statistics collection in the information_schema.QUERY_RESPONSE_TIME view. |
| ob_query_switch_leader_retry_timeout | Specifies the maximum retry time for a failed query, in microseconds (us). |
Load balancing-related
| Parameter | Description |
|---|---|
| enable_ls_leader_balance | Specifies whether to enable automatic leader balancing for log streams. |
| enable_gts_standalone | Specifies whether to enable the feature that allows a tenant's GTS service to exclusively use a group of units. |
| balancer_idle_time | Specifies the wake-up interval for background task threads during load balancing. |
| enable_rebalance | Specifies whether to enable automatic load balancing. |
| enable_transfer | Specifies whether to allow transfers within a tenant. This parameter is invalid when enable_rebalance is disabled. |
| partition_balance_schedule_interval | Specifies the partition balancing schedule cycle. |
Replica-related
| Parameter | Description |
|---|---|
| replica_parallel_migration_mode | Specifies the mode for parallel migration of log stream replicas. |
Scaling-related
| Parameter | Description |
|---|---|
| ls_scale_out_factor | The scaling-out factor for log streams, which controls the number of log streams per service node. |
Backup and restore-related
| Parameter | Description |
|---|---|
| log_restore_concurrency | Specifies the concurrency level for log restoration. |
| log_archive_concurrency | Specifies the concurrency level for log archiving. |
| backup_data_file_size | Specifies the maximum size of a single data backup file. |
Background execution threads
| Parameter | Description |
|---|---|
| ddl_thread_score | Specifies the number of threads used for DDL tasks. |
| compaction_low_thread_score | Specifies the number of threads used for low-priority major compactions. |
| compaction_high_thread_score | Specifies the number of threads used for high-priority major compactions. |
| compaction_mid_thread_score | Specifies the number of threads used for medium-priority major compactions. |
| ha_high_thread_score | Specifies the number of threads used for high-priority high-availability tasks. |
| ha_mid_thread_score | Specifies the number of threads used for medium-priority high-availability tasks. |
| ha_low_thread_score | Specifies the number of threads used for low-priority high-availability tasks. |
| ob_compaction_schedule_interval | Specifies the time interval between major compaction schedules. |
| compaction_dag_cnt_limit | Specifies the maximum number of DAGs that can be queued for major compaction. |
| compaction_schedule_tablet_batch_cnt | Specifies the maximum number of tablets to be scheduled in each batch for major compaction. |
| tenant_sql_login_thread_count | Specifies the number of threads for MySQL tenant login, that is, the number of mysql_queue threads. The default value of 0 indicates that the value of unit_min_cpu is used. |
| tenant_sql_net_thread_count | Specifies the number of threads for MySQL tenant I/O, that is, the number of sql_nio_server threads. The default value of 0 indicates that the value of unit_min_cpu is used. |
I/O
| Parameter | Description |
|---|---|
| io_category_config | Specifies the percentages of I/O requests of different categories. |
Compatibility
Note
The parameters in the following table take effect only in MySQL mode.
| Parameter | Description |
|---|---|
| enable_sql_extension | Specifies whether to enable the SQL extension feature for the tenant. |
| compatible | Specifies the compatibility behavior for the tenant. This parameter cannot be set. |
Routing
| Parameter | Description |
|---|---|
| ob_proxy_readonly_transaction_routing_policy | Specifies whether to route transactions based on read-only statements. |
LOB data
| Parameter | Description |
|---|---|
| lob_enable_block_cache_threshold | Specifies the threshold for caching LOB queries stored in OUTROW format. |
Memory-related
| Parameter name | Description |
|---|---|
| rpc_memory_limit_percentage | Specifies the maximum percentage of the total memory of a tenant that can be used for RPC. |
| range_optimizer_max_mem_size | Limits the memory used by the Query Range module. |
| query_memory_limit_percentage | Specifies the percentage of the total memory of a tenant that can be used for a single SQL statement. |
Disk space-related
| Parameter name | Description |
|---|---|
| temporary_file_max_disk_size | Specifies the maximum disk space that can be occupied by a temporary file on a single node of a tenant. |
OBKV-related
| Parameter name | Description |
|---|---|
| kv_ttl_duty_duration | Specifies the time period during which the TTL task is triggered daily. The TTL task is triggered once during this period. |
| kv_ttl_history_recycle_interval | Specifies the period for which the history records of the TTL task are retained. |
| enable_kv_ttl | Specifies whether to enable the TTL background task. This parameter is effective only for periodic TTL tasks. User commands are not affected by this parameter. |
| ttl_thread_score | Specifies the weight of the thread time slice used by the TTL task. |
| kv_group_commit_batch_size | Specifies the size of the batch operation executed in the group commit of OBKV. |
| kv_group_commit_rw_mode | Specifies the read/write mode for group commit. |
PL-related
| Parameter name | Description |
|---|---|
| plsql_code_type | Specifies the compilation type of PL/SQL code. |
| plsql_debug | Specifies whether to compile the code into a debug version. |
| plsql_optimize_level | Specifies the compilation optimization level. |
| plsql_v2_compatibility | Specifies whether to enable the feature of compiling and storing DDL statements of stored procedures. |
Others
| Parameter name | Description |
|---|---|
| zone_deploy_mode | Specifies the distribution mode of the tenant across zones. |
| enable_early_lock_release | Specifies whether to enable the early lock release feature. |
| workarea_size_policy | Specifies the strategy for manually or automatically adjusting the size of the SQL workarea. |
| open_cursors | Limits the number of cursors that can be opened simultaneously in a single session. |
| ob_enable_batched_multi_statement | Specifies whether to enable the grouped execution optimization for batch processing. |
| job_queue_processes | Specifies the maximum number of concurrent tasks that can run for each tenant to prevent resource contention. |
| default_auto_increment_mode | Specifies the default auto-increment mode for auto-increment columns. |
| default_enable_extended_rowid | Specifies whether to create tables in Extended ROWID mode. |
| dump_data_dictionary_to_log_interval | Specifies the interval for persisting the tenant data dictionary. |
| enable_user_defined_rewrite_rules | Specifies whether to enable the rewrite binding feature. |
| enable_ps_parameterize | Specifies whether to enable parameterization for PS statements during parsing. |
Transactions and transaction logs
| Parameter name | Description | |||||
|---|---|---|---|---|---|---|
| log_disk_utilization_limit_threshold | Set the tenant log disk utilization limit threshold. When the usage of the tenant log disk exceeds the total space multiplied by this threshold, logs cannot be written. | |||||
| log_disk_utilization_threshold | This parameter specifies the log disk utilization threshold for a tenant. When the tenant's log disk usage exceeds this threshold, log file reuse occurs. | |||||
| writing_throttling_maximum_duration | Specifies the time required to fill the remaining MemStore memory after write throttling is triggered. This parameter controls the writing speed by controlling the memory allocation. | |||||
| writing_throttling_trigger_percentage | This parameter specifies the maximum write speed in bytes per second (B/s). | |||||
| standby_db_fetch_log_rpc_timeout | Specifies the RPC timeout period when the standby database pulls logs. This parameter ensures that if a server in the primary database becomes unavailable, the standby database switches to another server. | |||||
| log_disk_throttling_percentage | The percentage of unrecoverable log disk space that triggers log write throttling. | |||||
| log_transport_compress_all | Used to specify whether to compress log data. | |||||
| log_transport_compress_func | The compressor used for log transport. | |||||
| clog_max_unconfirmed_log_count | Used to specify the maximum number of unconfirmed logs in the transaction module. | |||||
| clog_persistence_compress_func | ||||||
| enable_clog_persistence_compress | Specifies whether to enable log persistence compression. |
Lock-related
| Parameter | Description |
|---|---|
| enable_lock_priority | This parameter specifies whether to enable lock priority. |
System-related
| Parameter | Description |
|---|---|
| log_disk_throttling_maximum_duration | Adjusts the maximum time the logs are available after throttling is triggered. |
| ls_gc_delay_time | Used to set the delay period before the O&M engineer deletes the log stream. |
| standby_db_preferred_upstream_log_region | Configures the preferred region for synchronizing upstream logs in a physical standby tenant. |
| archive_lag_target | This parameter specifies the log archiving delay threshold for the tenant. |
User login
Note
The following parameters are available only in MySQL mode.
| Parameter name | Description |
|---|---|
| connection_control_failed_connections_threshold | Specifies the threshold for failed login attempts. |
| connection_control_min_connection_delay | Specifies the minimum lockout duration after exceeding the failed login threshold. |
| connection_control_max_connection_delay | Specifies the maximum lockout duration. The lockout duration does not increase beyond this value. |
Dump and major compaction
| Parameter name | Description |
|---|---|
| default_progressive_merge_num | Specifies the default number of progressive major compactions for a new table. |
| major_freeze_duty_time | Specifies the time when major compactions are triggered. |
| major_compact_trigger | Specifies the number of major compactions that trigger a global major compaction. |
| minor_compact_trigger | Specifies the threshold for triggering minor compactions. |
| undo_retention | Specifies the range of data versions to be retained, in seconds. During minor compactions, this parameter controls the recycling of data versions. |
| merger_check_interval | Specifies the scheduling interval for the major compaction status check thread. |
| freeze_trigger_percentage | Specifies the memory usage threshold for triggering a global freeze. |
| max_kept_major_version_number | Specifies the number of major compaction versions to be retained. |
| merge_stat_sampling_ratio | Specifies the sampling rate for data column statistics during major compactions. |
| merge_thread_count | Specifies the number of threads for daily major compactions. |
| merger_completion_percentage | Specifies the percentage threshold for the number of completed major compactions. When this threshold is reached, the current major compaction is considered complete. |
| merger_switch_leader_duration_time | Specifies the interval for batch leader switching during daily major compactions. |
| merger_warm_up_duration_time | Specifies the warm-up time for the new baseline data during major compactions. |
Arbitration service
| Parameter name | Description |
|---|---|
| arbitration_timeout | Specifies the timeout for triggering automatic downgrade. |
Cache-related
| Parameter name | Description |
|---|---|
| ob_deterministic_udf_cache_max_size | Specifies the maximum amount of memory that can be used by all deterministic UDFs in the cache pool during statement execution. |
Unsupported parameters
| Parameter name | Description |
|---|---|
| sql_work_area | Specifies the tenant's work area memory. |
| max_stale_time_for_weak_consistency | Specifies the maximum amount of stale data that can be read with weak consistency. |