OceanBase Database underwent architectural changes and restructuring in V4.x. As a result, many parameters or variables no longer function. V4.x removed and changed these invalid parameters or variables. For example, the minor_freeze_times parameter, which is used to trigger a major freeze, has been removed. Additionally, we have adjusted the default values of some parameters. In V4.x, the underlying system supports the capability of large transactions, and transactions are no longer affected by freeze operations. Therefore, we have changed the default value of freeze_trigger_percentage to 20%.
Changes related to parameters in V4.x
Replaced parameters
The following table lists parameters in V4.x that replace those in V3.x.
| Parameter (V3.x) | Replaced parameter (V4.x) | Description |
|---|---|---|
| backup_concurrency | ha_low_thread_score | The replaced parameter is a tenant-level parameter. |
| clog_disk_utilization_threshold | log_disk_utilization_threshold | The replaced parameter is a tenant-level parameter. |
| clog_transport_compress_func | log_transport_compress_func | The replaced parameter is a tenant-level parameter. |
| data_copy_concurrency, fast_recovery_concurrency, and restore_concurrency | ha_high_thread_score | The replaced parameter is a tenant-level parameter. |
| log_archive_checkpoint_interval | archive_lag_target | The replaced parameter is a tenant-level parameter. |
| merge_thread_count | compaction_low_thread_score | The replaced parameter is a tenant-level parameter. |
| migrate_concurrency , server_data_copy_out_concurrency, and server_data_copy_in_concurrency | ha_mid_thread_score | The replaced parameter is a tenant-level parameter. |
| sql_audit_memory_limit | ob_sql_audit_percentage | The parameter is replaced with a tenant variable and is no longer a configuration parameter. |
| minor_merge_concurrency | compaction_mid_thread_score | The replaced parameter is a tenant-level parameter. |
| clog_persistence_compress_func | log_storage_compress_func | The replaced parameter is a tenant-level parameter. |
| enable_clog_persistence_compress | log_storage_compress_all | The replaced parameter is a tenant-level parameter. |
Parameters whose names were changed
The following table lists the parameters whose names were changed in V4.x.
| Item name (V3.x) | Item name (V4.x) | Description |
|---|---|---|
| tableapi_transport_compress_func | kv_transport_compress_func |
|
Parameters whose scopes were changed
OceanBase Database adopts a multi-tenant architecture. Most users will create multiple tenants in the same cluster and manage them separately based on different business types. To meet the needs of users where each tenant represents a business unit, V4.x splits cluster-level capabilities to tenant level. For example, tenant-level backup, tenant-level minor compaction, and tenant-level major compaction are implemented.
The following table lists the parameters whose scopes were changed.
| Item name | Description |
|---|---|
| backup_data_file_size |
|
| enable_rebalance | The scope was changed from cluster level to tenant level starting from V4.2.0. |
| balancer_idle_time | The scope was changed from cluster level to tenant level starting from V4.2.0. |
| log_archive_concurrency | The scope was changed from cluster level to tenant level starting from V4.1.0. |
| log_restore_concurrency | The scope was changed from cluster level to tenant level starting from V4.1.0. |
| major_compact_trigger | The scope was changed from cluster level to tenant level starting from V4.0.0. |
| minor_compact_trigger | The scope was changed from cluster level to tenant level starting from V4.0.0. |
Parameters for changing the effective mode
Parameters are generally categorized into dynamic effective and restart effective modes. Most parameters adopt the dynamic effective mode, which means that no restart of the OBServer node is required for them to take effect.
The following table lists the parameters for changing the effective mode.
| Parameter | Description |
|---|---|
| server_cpu_quota_min |
|
| server_cpu_quota_max |
|
Parameters with changed default values
The following table lists the parameters with changed default values.
| Parameter | Description |
|---|---|
| kv_group_commit_batch_size | Starting from V4.3.5 BP1, the default value has been changed from 1 to 10. |
| direct_load_allow_fallback | Starting from V4.3.5, the default value has been changed from False to True. |
| memstore_limit_percentage |
|
| range_optimizer_max_mem_size |
|
| ls_gc_delay_time |
|
| enable_monotonic_weak_read | Starting from V4.2.1, the default value was changed from true to false. |
| location_refresh_thread_count | Starting from V4.2.0, the default value was changed from 4 to 2. |
| enable_record_trace_id | Starting from V4.2.0, the default value was changed from true to false. |
| plan_cache_evict_interval | Starting from V4.2.0, the default value was changed from 1s to 5s. |
| tenant_task_queue_size | Starting from V4.1.0, the default value was changed from 65536 to 16384. |
| server_cpu_quota_min |
|
| writing_throttling_maximum_duration | Starting from V4.0.0, the default value was changed from 1h to 2h. |
| writing_throttling_trigger_percentage | Starting from V4.0.0, the default value was changed from 100 to 60. |
| freeze_trigger_percentage | Starting from V4.0.0, the default value was changed from 70 to 20. |
Parameters with changed value ranges
The following table lists the parameters with changed value ranges.
| Parameter | Description |
|---|---|
| ob_startup_mode | Added SHARED_STORAGE to the value range, starting from V4.3.4. |
| large_query_threshold |
|
| memstore_limit_percentage |
|
| range_optimizer_max_mem_size |
|
| job_queue_processes |
|
| memory_limit_percentage | Starting from V4.2.1, the value range changed from [10, 90] to [10, 95]. |
| cpu_quota_concurrency | Starting from V4.2.0, the value range changed from [1, 10] to [1, 20]. |
| memory_limit | Starting from V4.1.0, the value range changed from [4 GB, +∞) to [1 GB, +∞). |
| server_cpu_quota_min |
|
Parameters with changed semantics
The following table lists parameters whose semantics were changed in V4.x.
| Parameter | Description |
|---|---|
| datafile_maxsize | From V4.3.4, in Shared-Nothing (SN) mode, this parameter retains its original semantics; in Shared-Storage (SS) mode, this parameter is meaningless. |
| datafile_next | From V4.3.4, in Shared-Nothing (SN) mode, this parameter retains its original semantics; in Shared-Storage (SS) mode, this parameter is meaningless. |
| datafile_disk_percentage | From V4.3.4, in Shared-Nothing (SN) mode, this parameter retains its original semantics; in Shared-Storage (SS) mode, this parameter specifies the percentage of the local available cache space of the disk space. |
| datafile_size | From V4.3.4, in Shared-Nothing (SN) mode, this parameter retains its original semantics; in Shared-Storage (SS) mode, this parameter specifies the size of the local cache space. |
New parameters
The following table lists the new parameters introduced in V4.x.
| Parameter | Introduced version | Description |
|---|---|---|
| enable_lock_priority | V4.3.5 BP2 | The table lock priority switch. |
| enable_adaptive_plan_cache | V4.3.5 BP2 | Controls whether the tenant enables the adaptive capability of the plan cache. |
| global_index_auto_split_policy | V4.3.5 BP2 | Controls whether newly created global indexes enable the automatic partitioning feature. |
| default_storage_cache_policy | V4.3.5 BP2 | Configures the default caching policy. |
| enable_manual_storage_cache_policy | V4.3.5 BP2 | Enables user-specified manual hotspot caching policies. |
| suspend_storage_cache_task | V4.3.5 BP2 | Sets whether to suspend background caching tasks. |
| clog_io_isolation_mode | V4.3.5 BP2 | Determines whether the I/O requests of the clog disk are controlled by resource isolation, based on whether the clog disk and data disk are independent. Users can flexibly adjust the value of this parameter according to the actual system deployment to balance performance and resource utilization. |
| default_table_organization | V4.3.5 BP1 | Allows setting the default table organization mode for tables. |
| px_node_policy | V4.3.5 BP1 | Determines the candidate pool for PX computing nodes. |
| ob_enable_java_env | V4.3.5 BP1 | Controls whether to enable the Java environment required for external table capabilities such as HDFS/MaxCompute (ODPS). |
| ob_java_home | V4.3.5 BP1 | Sets the Java home path required for JNI runtime, which needs to be configured when ob_enable_java_env is enabled. |
| ob_java_opts | V4.3.5 BP1 | Sets JVM startup options, such as memory size and garbage collection algorithms, which need to be configured when ob_enable_java_env is enabled. |
| ob_java_connector_path | V4.3.5 BP1 | Sets the path of the jar package required by the external table connector, which needs to be configured when ob_enable_java_env is enabled. |
| temporary_file_max_disk_size | V4.3.5 BP1 | Sets the maximum disk space that temporary files can occupy within a single node for a tenant. |
| package_state_sync_max_size | V4.3.5 BP1 | Controls the maximum length of package state synchronization variable values. If the value exceeds the configured limit, the package variables will not be synchronized. |
| unit_gc_wait_time |
|
Specifies the maximum wait time for Unit GC. If the maximum wait time is exceeded, GC is forced. |
| recover_table_concurrency |
|
Sets the maximum number of tables that can be recovered in parallel during the cross-tenant table import phase of table-level recovery. |
| recover_table_dop |
|
Sets the maximum number of tables that can be recovered in parallel for a single table during the cross-tenant table import phase of table-level recovery. |
| query_memory_limit_percentage |
|
Defines the percentage of tenant memory that can be used by a single SQL query. |
| replica_parallel_migration_mode |
|
Specifies the mode for parallel migration of replica logs. |
| sts_credential |
|
Specifies the credentials required to access the STS service provided by OCP. |
| arbitration_degradation_policy | V4.3.4 | Configures the policy for automatic degradation. |
| kv_hbase_client_scanner_timeout_period | V4.3.4 | Specifies the timeout period for OBKV-HBase streaming queries. |
| default_load_mode | V4.3.4 | Defines the hint to be used when no hint is specified during a data loading operation. |
| direct_load_allow_fallback | V4.3.4 | Specifies whether an error is raised when direct load is not supported during a data loading operation. |
| enable_auto_split | V4.3.4 | Specifies whether automatic partitioning is enabled for the table. |
| auto_split_tablet_size | V4.3.4 | Specifies the threshold for triggering partition splitting after automatic partitioning is enabled for the tenant. |
| sync_io_thread_count | V4.3.4 | Specifies the number of threads for synchronous IO requests. |
| ob_encoding_granularity | V4.3.3 | Specifies the percentage limit of memory resources that the vector index module can use. |
| ob_storage_s3_url_encode_type | V4.3.3 | Specifies whether the URL encoding method for S3 requests complies with the Rfc3986 standard. |
| ob_vector_memory_limit_percentage | V4.3.3 | Specifies the memory usage threshold (as a percentage) for the vector index module. |
| storage_rowsets_size | V4.3.2 | Specifies the number of rows processed in a single vectorized batch by the columnar engine. |
| alert_log_level |
|
Specifies the log level for alert messages. |
| enable_global_background_resource_isolation |
|
Specifies whether to enable global foreground and background resource isolation. |
| global_background_cpu_quota |
|
Specifies the number of CPU cores allocated for background tasks when global foreground and background resource isolation is enabled. |
| choose_migration_source_policy |
|
Specifies the priority policy for selecting source replicas during migration. |
| lob_enable_block_cache_threshold |
|
Specifies the threshold for caching OUTROW LOB queries. |
| spill_compression_codec | V4.3.1 | Specifies the compression algorithm type for data spill compression during SQL execution. |
| max_partition_num |
|
Specifies the maximum number of partitions allowed in MySQL mode. |
| log_storage_compress_all |
|
Specifies whether to enable clog storage compression. |
| syslog_compress_func |
|
Specifies the compression algorithm for system logs. |
| syslog_disk_size |
|
Specifies the disk space limit for system logs. |
| syslog_file_uncompressed_count |
|
Specifies the number of uncompressed system log files. |
| log_storage_compress_func |
|
Specifies the compression algorithm for clog storage compression. |
| enable_dblink |
|
Specifies whether to enable the DBLink feature. |
| data_disk_write_limit_percentage |
|
Specifies the percentage limit for data disk writes. |
| strict_check_os_params |
|
Specifies whether to enable the function to check OS configuration parameters. |
| default_table_store_format | V4.3.0 | Specifies the default format for creating tables in user tenants, including row storage, pure column storage, and redundant row-column storage. |
| enable_rpc_authentication_bypass | V4.3.0 | Specifies whether to allow the OMS migration service and OBKV service to bypass RPC security authentication to connect to the cluster when RPC security authentication is enabled in the OBServer cluster. |
| sql_protocol_min_tls_version | V4.2.1 | Specifies the minimum version of the SSL/TLS protocol used for SQL statements during SSL connections. |
| compaction_dag_cnt_limit | V4.2.1 | Specifies the upper limit for the number of DAGs in the Compaction DAG queue. |
| compaction_schedule_tablet_batch_cnt | V4.2.1 | Specifies the maximum number of partitions scheduled per batch during Compaction scheduling. |
| enable_transfer | V4.2.1 | Specifies whether to allow Transfer operations within the tenant. |
| ttl_thread_score | V4.2.1 | Specifies the number of worker threads used by TTL tasks. |
| local_ip | V4.2.0 | Specifies the IP address of the machine where ObServer is installed during cluster deployment. |
| observer_id | V4.2.0 | Specifies the unique identifier assigned by RS to the OBServer node in the cluster. |
| standby_fetch_log_bandwidth_limit | V4.2.0 | Specifies the maximum total bandwidth per second that all servers in the standby tenant's cluster can use to synchronize logs from the primary tenant. |
| storage_meta_cache_priority | V4.2.0 | Specifies the priority of storing Meta Cache in kvcache. |
| archive_lag_target | V4.2.0 | Specifies the log archiving delay time for the tenant. |
| log_disk_throttling_maximum_duration | V4.2.0 | Specifies the maximum available time for the log disk after triggering log throttling. |
| log_disk_throttling_percentage | V4.2.0 | Specifies the percentage of unrecoverable log disk space that triggers log write throttling. |
| ls_gc_delay_time | V4.2.0 | Specifies the delay time for deleting tenant log streams. |
| partition_balance_schedule_interval | V4.2.0 | Specifies the scheduling interval for partition balance. |
| range_optimizer_max_mem_size | V4.2.0 | Limits the memory used by the Query Range module. |
| standby_db_fetch_log_rpc_timeout | V4.2.0 | Specifies the RPC timeout for log fetching in standby databases to control the detection of unavailable servers in the primary database and switching to other servers. |
| standby_db_preferred_upstream_log_region | V4.1.0 | Specifies the preferred region for upstream log synchronization in physical standby database scenarios. |
| log_storage_warning_tolerance_time | V4.1.0 | Specifies the time from log disk I/O failure to marking the disk as faulty and triggering a primary switch. |
| ob_startup_mode | V4.1.0 | Specifies the startup mode of the OBServer node, which can only be modified during the first startup. |
| sql_net_thread_count | V4.1.0 | Specifies the number of IO threads in the MySQL cluster, i.e., the number of global_sql_nio_server threads. |
| arbitration_timeout | V4.1.0 | Specifies the timeout for triggering automatic degradation. |
| dump_data_dictionary_to_log_interval | V4.1.0 | Controls the persistence interval of the tenant's data dictionary. |
| enable_user_defined_rewrite_rules | V4.1.0 | Specifies whether to enable user-defined rewrite rules. |
| log_transport_compress_all | V4.1.0 | Specifies whether to use compression for log transport. |
| log_transport_compress_func | V4.1.0 | Specifies the compression algorithm for log transport. |
| rpc_memory_limit_percentage | V4.1.0 | Specifies the maximum percentage of tenant memory that RPC can use. |
| tenant_sql_login_thread_count | V4.1.0 | Specifies the number of login threads for MySQL tenants, i.e., the number of mysql_queue threads. |
| tenant_sql_net_thread_count | V4.1.0 | Specifies the number of IO threads for MySQL tenants, i.e., the number of sql_nio_server threads. |
| log_disk_percentage | V4.0.0 | Specifies the percentage of the total disk space occupied by Redo logs on its disk. |
| log_disk_size | V4.0.0 | Specifies the size of the Redo log disk, i.e., the total log disk space that this OBServer can use. |
| ha_high_thread_score | V4.0.0 | Specifies the current number of working threads for high-priority high-availability threads. |
| ha_low_thread_score | V4.0.0 | Specifies the current number of working threads for low-priority high-availability threads. |
| ha_mid_thread_score | V4.0.0 | Specifies the current number of working threads for medium-priority high-availability threads. |
| query_memory_limit_percentage |
|
Specifies the percentage of tenant memory that a single SQL query can use. |
Deprecated configurations
The following table lists the configurations deprecated in V4.x.
| Configuration | Description |
|---|---|
| global_write_halt_residual_memory | This configuration is deprecated and will be removed in V4.2.0. |
| max_px_worker_count | This configuration is deprecated and will be removed in V4.2.0. |
| plan_cache_high_watermark | This configuration is deprecated and will be removed in V4.2.0. |
| plan_cache_low_watermark | This configuration is deprecated and will be removed in V4.2.0. |
| rootservice_memory_limit | This configuration is deprecated and will be removed in V4.2.0. |
| system_trace_level | This configuration is deprecated and will be removed in V4.2.0. |
| token_reserved_percentage | This configuration is deprecated and will be removed in V4.2.0. |
| trace_log_sampling_interval | This configuration is deprecated and will be removed in V4.2.0. |
| io_category_config | This configuration is deprecated and will be removed in V4.2.0. |
| auto_broadcast_location_cache_rate_limit | This configuration is deprecated and will be removed in V4.0.0. |
| auto_leader_switch_interval | This configuration is deprecated and will be removed in V4.0.0. |
| auto_refresh_location_cache_rate_limit | This configuration is deprecated and will be removed in V4.0.0. |
| backup_backup_dest | This configuration is deprecated and will be removed in V4.0.0. |
| backup_backup_dest_option | This configuration is deprecated and will be removed in V4.0.0. |
| backup_dest_option | This configuration is deprecated and will be removed in V4.0.0. |
| backup_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration ha_low_thread_score is used to replace it in V4.0.0. |
| backup_dest | This configuration is deprecated and will be removed in V4.0.0. |
| backup_log_archive_option | This configuration is deprecated and will be removed in V4.0.0. |
| backup_net_limit | This configuration is deprecated and will be removed in V4.0.0. |
| backup_recovery_window | This configuration is deprecated and will be removed in V4.0.0. |
| backup_region | This configuration is deprecated and will be removed in V4.0.0. |
| backup_zone | This configuration is deprecated and will be removed in V4.0.0. |
| balance_blacklist_failure_threshold | This configuration is deprecated and will be removed in V4.0.0. |
| balance_blacklist_retry_interval | This configuration is deprecated and will be removed in V4.0.0. |
| balancer_emergency_percentage | This configuration is deprecated and will be removed in V4.0.0. |
| balancer_timeout_check_interval | This configuration is deprecated and will be removed in V4.0.0. |
| clog_disk_utilization_threshold | This configuration is deprecated and will be removed in V4.0.0. The new configuration log_disk_utilization_threshold is used to replace it in V4.0.0. |
| clog_expire_days | This configuration is deprecated and will be removed in V4.0.0. |
| clog_cache_priority | This configuration is deprecated and will be removed in V4.0.0. |
| clog_disk_usage_limit_percentage | This configuration is deprecated and will be removed in V4.0.0. |
| clog_transport_compress_func | This configuration is deprecated and will be removed in V4.0.0. The feature is not supported in V4.0.0. The new configuration log_transport_compress_func is used to replace it in V4.1.0. |
| clog_max_unconfirmed_log_count | This configuration is deprecated and will be removed in V4.0.0. The feature is no longer applicable. |
| clog_persistence_compress_func | This configuration is deprecated and will be removed in V4.0.0. The feature is not supported in V4.0.0. The new configuration log_storage_compress_func is used to replace it in V4.2.1 (excluding V4.3.0). |
| cpu_reserved | This configuration is deprecated and will be removed in V4.0.0. |
| data_copy_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration ha_high_thread_score is used to replace it in V4.0.0. |
| default_transport_compress_func | This configuration is deprecated and will be removed in V4.0.0. |
| election_cpu_quota | This configuration is deprecated and will be removed in V4.0.0. |
| election_blacklist_interval | This configuration is deprecated and will be removed in V4.0.0. |
| enable_auto_refresh_location_cache | This configuration is deprecated and will be removed in V4.0.0. |
| enable_auto_leader_switch | This configuration is deprecated and will be removed in V4.0.0. |
| enable_clog_persistence_compress | This configuration is deprecated and will be removed in V4.0.0. The feature is not supported in V4.0.0. The new configuration log_storage_compress_all is used to replace it in V4.2.1 (excluding V4.3.0). |
| enable_global_freeze_trigger | This configuration is deprecated and will be removed in V4.0.0. |
| enable_log_archive | This configuration is deprecated and will be removed in V4.0.0. |
| enable_election_group | This configuration is deprecated and will be removed in V4.0.0. |
| enable_merge_by_turn | This configuration is deprecated and will be removed in V4.0.0. |
| enable_manual_merge | This configuration is deprecated and will be removed in V4.0.0. |
| enable_one_phase_commit | This configuration is deprecated and will be removed in V4.0.0. |
| enable_pg | This configuration is deprecated and will be removed in V4.0.0. |
| enable_separate_sys_clog | This configuration is deprecated and will be removed in V4.0.0. |
| enable_smooth_leader_switch | This configuration is deprecated and will be removed in V4.0.0. |
| enable_rootservice_standalone | This configuration is deprecated and will be removed in V4.0.0. |
| fast_recovery_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration ha_high_thread_score is used to replace it in V4.0.0. |
| flush_log_at_trx_commit | This configuration is deprecated and will be removed in V4.0.0. |
| gc_wait_archive | This configuration is deprecated and will be removed in V4.0.0. |
| global_index_build_single_replica_timeout | This configuration is deprecated and will be removed in V4.0.0. |
| global_major_freeze_residual_memory | This configuration is deprecated and will be removed in V4.0.0. |
| get_leader_candidate_rpc_timeout | This configuration is deprecated and will be removed in V4.0.0. |
| ignore_replica_checksum_error | This configuration is deprecated and will be removed in V4.0.0. |
| index_clog_cache_priority | This configuration is deprecated and will be removed in V4.0.0. |
| index_info_block_cache_priority | This configuration is deprecated and will be removed in V4.0.0. |
| index_cache_priority | This configuration is deprecated and will be removed in V4.0.0. |
| ilog_index_expire_time | This configuration is deprecated and will be removed in V4.0.0. |
| location_cache_priority | This configuration is deprecated and will be removed in V4.0.0. |
| location_cache_expire_time | This configuration is deprecated and will be removed in V4.0.0. |
| log_archive_batch_buffer_limit | This configuration is deprecated and will be removed in V4.0.0. |
| log_archive_checkpoint_interval | This configuration is deprecated and will be removed in V4.0.0. The new configuration archive_lag_target is used to replace it in V4.0.0. |
| max_kept_major_version_number | This configuration is deprecated and will be removed in V4.0.0. |
| merge_stat_sampling_ratio | This configuration is deprecated and will be removed in V4.0.0. |
| merge_thread_count | This configuration is deprecated and will be removed in V4.0.0. The new configuration compaction_low_thread_score is used to replace it in V4.0.0. |
| merger_completion_percentage | This configuration is deprecated and will be removed in V4.0.0. |
| merger_switch_leader_duration_time | This configuration is deprecated and will be removed in V4.0.0. |
| merger_warm_up_duration_time | This configuration is deprecated and will be removed in V4.0.0. |
| migrate_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration ha_mid_thread_score is used to replace it in V4.0.0. |
| minor_deferred_gc_time | This configuration is deprecated and will be removed in V4.0.0. |
| minor_freeze_times | This configuration is deprecated and will be removed in V4.0.0. The new configuration major_compact_trigger is used to replace it in V4.0.0. |
| minor_merge_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration compaction_mid_thread_score is used to replace it in V4.0.0. |
| minor_warm_up_duration_time | This configuration is deprecated and will be removed in V4.0.0. |
| multiblock_read_gap_size | This configuration is deprecated and will be removed in V4.0.0. |
| multiblock_read_size | This configuration is deprecated and will be removed in V4.0.0. |
| ob_esi_rpc_port | This configuration is deprecated and will be removed in V4.0.0. |
| enable_ob_esi_process | This configuration is deprecated and will be removed in V4.0.0. |
| ob_esi_session_timeout | This configuration is deprecated and will be removed in V4.0.0. |
| ob_esi_io_concurrency | This configuration is deprecated and will be removed in V4.0.0. |
| ob_esi_memory_limit | This configuration is deprecated and will be removed in V4.0.0. |
| ob_esi_syslog_level | This configuration is deprecated and will be removed in V4.0.0. |
| ob_esi_max_syslog_file_count | This configuration is deprecated and will be removed in V4.0.0. |
| ofs_list | This configuration is deprecated and will be removed in V4.0.0. |
| partition_table_check_interval | This configuration is deprecated and will be removed in V4.0.0. |
| rebuild_replica_data_lag_threshold | This configuration is deprecated and will be removed in V4.0.0. |
| replica_safe_remove_time | This configuration is deprecated and will be removed in V4.0.0. |
| resource_soft_limit | This configuration is deprecated and will be removed in V4.0.0. |
| restore_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration ha_high_thread_score is used to replace it in V4.0.0. |
| row_purge_thread_count | This configuration is deprecated and will be removed in V4.0.0. |
| server_data_copy_out_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration ha_mid_thread_score is used to replace it in V4.0.0. |
| server_data_copy_in_concurrency | This configuration is deprecated and will be removed in V4.0.0. The new configuration ha_mid_thread_score is used to replace it in V4.0.0. |
| sql_audit_memory_limit | This configuration is deprecated and will be removed in V4.0.0. The new variable ob_sql_audit_percentage is used to replace it in V4.0.0. |
| switchover_process_thread_count | This configuration is deprecated and will be removed in V4.0.0. |
| sys_bkgd_io_high_percentage | This configuration is deprecated and will be removed in V4.0.0. |
| sys_bkgd_io_low_percentage | This configuration is deprecated and will be removed in V4.0.0. |
| sys_cpu_limit_trigger | This configuration is deprecated and will be removed in V4.0.0. |
| system_cpu_quota | This configuration is deprecated and will be removed in V4.0.0. |
| tenant_groups | This configuration is deprecated and will be removed in V4.0.0. |
| trx_force_kill_threshold | This configuration is deprecated and will be removed in V4.0.0. |
| unit_balance_resource_weight | This configuration is deprecated and will be removed in V4.0.0. |
| user_iort_up_percentage | This configuration is deprecated and will be removed in V4.0.0. |
| user_tab_col_stat_cache_priority | This configuration is deprecated and will be removed in V4.0.0. |
| wait_leader_batch_count | This configuration is deprecated and will be removed in V4.0.0. |
| zone_merge_concurrency | This configuration is deprecated and will be removed in V4.0.0. |
| zone_merge_order | This configuration is deprecated and will be removed in V4.0.0. |
| zone_merge_timeout | This configuration is deprecated and will be removed in V4.0.0. |
Changes related to system variables in V4.x
To better adapt to user business scenarios, OceanBase Database has optimized and adjusted the default values and value ranges of tenant variables. Specifically, in earlier versions, undo_retention was introduced as a system variable, but starting from V4.0.0, undo_retention has been adjusted to a tenant-level parameter.
System variables with changed default values
The following table lists system variables with changed default values.
| Variable name | Description |
|---|---|
| ob_default_lob_inrow_threshold |
|
| sql_mode |
|
| optimizer_features_enable |
|
| secure_file_priv | Starting from version V4.2.1, the default value has been changed from NULL to "". |
| max_allowed_packet | Starting from version V4.2.1, the default value has been increased from 4194304 to 16777216. |
| ob_max_read_stale_time | Starting from version V4.1.0, the default value has been changed from 5000000 to -1. |
| ob_trx_idle_timeout | Starting from V4.0.0, the default value has been changed from 120 seconds to 1 day. |
| ob_trx_timeout | Starting from V4.0.0, the default value has been changed from 100 seconds to 1 day. |
System variables whose value ranges or meanings are changed
The following table lists system variables whose value ranges or meanings are changed.
| Variable | Description |
|---|---|
| secure_file_priv | From V4.2.0, the meanings of the enumerated values empty string ("") and NULL are changed from "unrestricted" to "import and export disabled". |
| ob_max_read_stale_time | From V4.1.0, the value range is changed from [0, 9223372036854775807] to [-1, 9223372036854775807]. |
System variables whose privilege requirements are changed
The following table lists system variables whose privilege requirements are changed.
| Variable | Description |
|---|---|
| secure_file_priv | From V4.2.0, the variable can only be modified through a local Unix socket connection. |
New system variables
The following table lists the system variables introduced in V4.x.
| Variable name | Introduced version | Description |
|---|---|---|
| event_scheduler | V4.3.5 BP2 | Determines whether the event scheduler is enabled and running on the server. |
| ob_enable_ps_parameter_anonymous_block | V4.3.5 BP2 | Controls whether anonymous blocks and call statements in PS mode are parameterized during parsing. |
| ob_sparse_drop_ratio_search | V4.3.5 BP2 | Sets the default extra info threshold for HNSW indexes. |
| ob_ivf_nprobes | V4.3.5 BP1 | Specifies how many nearest cluster centers to search during vector index queries. |
| mview_refresh_dop | V4.3.5 BP1 | Controls the default refresh parallelism for materialized views. |
| enable_optimizer_rowgoal | V4.3.5 BP1 | Controls whether the optimizer considers row count goals (e.g., LIMIT operators) during cardinality estimation. |
| pid_file |
|
Specifies the pathname of the file where the server writes its process ID. |
| port |
|
Sets the port number for the server to listen for TCP/IP connections during OBServer node deployment. |
| socket |
|
Specifies the name of the local client connection socket file. |
| ob_hnsw_ef_search | V4.3.3 | Sets the number of neighbor nodes considered during HNSW vector index searches. |
| ob_table_access_policy | V4.3.3 | Controls the optimizer to prioritize specific storage formats when generating base table plans. |
| cardinality_estimation_model |
|
Controls the correlation model used by the optimizer for row estimation. |
| activate_all_roles_on_login |
|
Controls whether all roles are automatically activated by default upon login. |
| innodb_stats_persistent |
|
Controls whether InnoDB index statistics are persisted to disk. |
| ob_compatibility_control |
|
Controls behavior modes in case of compatibility conflicts between MYSQL5.7 and MYSQL8.0. |
| ob_compatibility_version |
|
Controls the OceanBase database version for functional compatibility changes. |
| ob_security_version |
|
Controls the OceanBase database version for security feature compatibility. |
| automatic_sp_privileges |
|
Sets whether ALTER and EXECUTE privileges are automatically granted for stored procedures. |
| lc_time_names |
|
Controls the language used for displaying date and month names and abbreviations. |
| ob_enable_pl_cache |
|
Controls whether the PL cache module is enabled. |
| optimizer_dynamic_sampling | V4.2.0 | Controls the level of dynamic sampling. |
| optimizer_features_enable | V4.2.0 | Enables optimizer features of different OceanBase versions. |
| parallel_degree_limit | V4.2.0 | Sets the upper limit of parallelism chosen by the optimizer when using the Auto DOP strategy. |
| parallel_degree_policy | V4.2.0 | Sets the parallelism selection strategy. |
| parallel_min_scan_time_threshold | V4.2.0 | A parameter used in the Auto DOP strategy to evaluate the minimum execution time for parallel processing of base table scans. |
| runtime_filter_type | V4.2.0 | Sets the tenant-level Runtime Filter type. |
| runtime_filter_wait_time_ms | V4.2.0 | Sets the maximum wait time for the Runtime Filter. |
| runtime_filter_max_in_num | V4.2.0 | Sets the number of distinct values (NDVs) in a column for the Runtime In Filter. |
| runtime_bloom_filter_max_size | V4.2.0 | Sets the maximum memory usage for the Runtime Bloom Filter, in bytes. |
| cte_max_recursion_depth | V4.1.0 | Sets the maximum recursion depth for Common Table Expressions (CTEs). The server will terminate any operation that exceeds this value. |
| ob_max_read_stale_time | V4.1.0 | Sets the maximum latency threshold (in microseconds) for weak read queries. |
| regexp_stack_limit | V4.1.0 | Sets the maximum available memory for the internal stack during regular expression matching operations, with the default unit being bytes. |
| ob_enable_show_trace | V4.1.0 | Controls whether to enable Show Trace logs. |
| cursor_sharing | V4.0.0 | Determines whether SQL statements are parameterized during processing. |
| innodb_strict_mode | V4.0.0 | Sets the SQL checking mode for specific syntax. |
| log_row_value_options | V4.0.0 | Controls whether large objects (LOBs) use partial updates. |
| ob_enable_rich_error_msg | V4.0.0 | Controls whether to display additional information such as svr_ip, time, and trace_id when SQL execution errors occur. |
Deprecated system variables
The following table lists the system variables deprecated in V4.x.
| Variable name | Description |
|---|---|
| ob_enable_trace_log | Removed starting from V4.1.0 due to architecture upgrades. |
| ob_create_table_strict_mode | Removed starting from V4.0.0 due to architecture upgrades. |
| ob_enable_blk_nestedloop_join | Removed starting from V4.0.0 as the corresponding functionality is no longer applicable due to logic changes. |
| ob_enable_hash_group_by | Removed starting from V4.0.0 due to changes in implementation. |
| ob_timestamp_service | Removed starting from V4.0.0 due to architecture upgrades. |