OceanBase Database V4.x has undergone architectural changes and restructuring. As a result, many configuration parameters and variables are no longer applicable. In V4.x, these obsolete parameters and variables have been removed or modified. For example, the parameter minor_freeze_times used to trigger a major freeze has been deleted. Additionally, some default values of parameters have been adjusted. For example, in V4.x, the system supports large transactions at the underlying layer, and transactions are no longer affected by freeze operations. Therefore, the default value of freeze_trigger_percentage has been adjusted to 20%.
Changes to configuration items in V4.x
Replaced configuration items
The following table lists the configuration items in V4.x that replace those in V3.x.
| Configuration item (V3.x) | Replaced configuration item (V4.x) | Description |
|---|---|---|
| backup_concurrency | ha_low_thread_score | The replaced configuration item is at the tenant level. |
| clog_disk_utilization_threshold | log_disk_utilization_threshold | The replaced configuration item is at the tenant level. |
| clog_transport_compress_func | log_transport_compress_func | The replaced configuration item is at the tenant level. |
| data_copy_concurrency、fast_recovery_concurrency、restore_concurrency | ha_high_thread_score | The replaced configuration item is at the tenant level. |
| log_archive_checkpoint_interval | archive_lag_target | The replaced configuration item is at the tenant level. |
| merge_thread_count | compaction_low_thread_score | The replaced configuration item is at the tenant level. |
| migrate_concurrency 、server_data_copy_out_concurrency、server_data_copy_in_concurrency | ha_mid_thread_score | The replaced configuration item is at the tenant level. |
| sql_audit_memory_limit | ob_sql_audit_percentage | The configuration item is replaced by a tenant variable. |
| minor_merge_concurrency | compaction_mid_thread_score | The replaced configuration item is at the tenant level. |
| clog_persistence_compress_func | log_storage_compress_func | The replaced configuration item is at the tenant level. |
| enable_clog_persistence_compress | log_storage_compress_all | The replaced configuration item is at the tenant level. |
Configuration items with changed names
The following table lists the configuration items whose names have changed in V4.x.
| Configuration item (V3.x) | Configuration item (V4.x) | Description |
|---|---|---|
| tableapi_transport_compress_func | kv_transport_compress_func |
|
Configuration items with changed scopes
OceanBase Database is a multi-tenant architecture. Most users create multiple tenants within the same cluster and manage them based on their business types. To meet the requirement of having one tenant represent one business unit, in V4.x, cluster-level capabilities are split into tenant-level capabilities. For example, tenant-level backup and tenant-level major compactions.
The following table lists the configuration items whose scopes have changed.
| Configuration item | Description |
|---|---|
| backup_data_file_size |
|
| enable_rebalance | Starting from V4.2.0, it was changed from cluster level to tenant level. |
| balancer_idle_time | Starting from V4.2.0, it was changed from cluster level to tenant level. |
| log_archive_concurrency | Starting from V4.1.0, it was changed from cluster level to tenant level. |
| log_restore_concurrency | Starting from V4.1.0, it was changed from cluster level to tenant level. |
| major_compact_trigger | Starting from V4.0.0, it was changed from cluster level to tenant level. |
| minor_compact_trigger | Starting from V4.0.0, it was changed from cluster level to tenant level. |
Configuration items with changed effective modes
Configuration items are generally divided into dynamic effective mode and restart effective mode. Most configuration items are in dynamic effective mode, which means they take effect without the need to restart the OBServer node.
The following table lists the configuration items whose effective modes have changed.
| Configuration item | Description |
|---|---|
| net_thread_count | Starting from V4.4.0, the effective mode was changed from restart effective to immediate effective. |
| server_cpu_quota_min |
|
| server_cpu_quota_max |
|
Configuration items for changing the default values
The following table lists the configuration items for changing the default values.
| Configuration item name | Description |
|---|---|
| compaction_dag_cnt_limit | Starting from V4.4.0, the default value is changed from 15000 to 50000. |
| kv_group_commit_batch_size | Starting from V4.3.5 BP1, the default value is changed from 1 to 10 for V4.3.5. |
| direct_load_allow_fallback | Starting from V4.3.5, the default value is 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 is changed from true to false. |
| location_refresh_thread_count | Starting from V4.2.0, the default value is changed from 4 to 2. |
| enable_record_trace_id | Starting from V4.2.0, the default value is changed from true to false. |
| plan_cache_evict_interval | Starting from V4.2.0, the default value is changed from 1s to 5s. |
| tenant_task_queue_size | Starting from V4.1.0, the default value is changed from 65536 to 16384. |
| server_cpu_quota_min |
|
| writing_throttling_maximum_duration | Starting from V4.0.0, the default value is changed from 1h to 2h. |
| writing_throttling_trigger_percentage | Starting from V4.0.0, the default value is changed from 100 to 60. |
| freeze_trigger_percentage | Starting from V4.0.0, the default value is changed from 70 to 20. |
Configuration items for changing the value range
The following table lists the configuration items for changing the value range.
| Configuration item name | Description |
|---|---|
| compaction_schedule_tablet_batch_cnt | Starting from V4.4.0, the value range is adjusted from [10000, 200000] to [10000, 500000]. |
| compaction_dag_cnt_limit | Starting from V4.4.0, the value range is adjusted from [10000, 200000] to [10000, 500000]. |
| net_thread_count | Starting from V4.3.5 BP2, the value range is adjusted from [0, 64] to [0, 128]. |
| ob_startup_mode | Starting from V4.3.4, the value range is adjusted to include SHARED_STORAGE. |
| 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 is adjusted from [10, 90] to [10, 95]. |
| cpu_quota_concurrency | Starting from V4.2.0, the value range is adjusted from [1,10] to [1,20]. |
| memory_limit | Starting from V4.1.0, the value range is adjusted from [4G, +∞) to [1G, +∞). |
| server_cpu_quota_min |
|
Configuration items whose semantics have changed
The following table lists the configuration items whose semantics have changed in V4.x.
| Configuration item name | Description |
|---|---|
| datafile_maxsize | Starting from V4.3.4, in Shared-Nothing (SN) mode, the semantics of this configuration item remain unchanged. In Shared-Storage (SS) mode, this configuration item is no longer meaningful. |
| datafile_next | Starting from V4.3.4, in Shared-Nothing (SN) mode, the semantics of this configuration item remain unchanged. In Shared-Storage (SS) mode, this configuration item is no longer meaningful. |
| datafile_disk_percentage | Starting from V4.3.4, in Shared-Nothing (SN) mode, the semantics of this configuration item remain unchanged. In Shared-Storage (SS) mode, this configuration item is used to set the percentage of local cache space available on the disk. |
| datafile_size | Starting from V4.3.4, in Shared-Nothing (SN) mode, the semantics of this configuration item remain unchanged. In Shared-Storage (SS) mode, this configuration item is used to set the size of the local cache space. |
New configuration items
The following table lists the new configuration items in V4.x.
| Configuration item | Introduced in | Description |
|---|---|---|
| enable_ls_leader_balance |
|
Specifies whether to enable the automatic balancing of log stream leaders. |
| enable_gts_standalone |
|
Specifies whether to enable the feature that allows a tenant to use a dedicated group of units for the GTS service. |
| zone_deploy_mode |
|
Specifies the distribution mode of a tenant across zones. |
| mds_minor_compact_trigger | V4.4.1 | Specifies the number of SSTables that triggers an MDS minor compaction. |
| mds_compaction_mid_thread_score | V4.4.1 | Specifies the number of DAG (Direct Acyclic Graph) threads for MDS compactions with medium priority. |
| mds_compaction_high_thread_score | V4.4.1 | Specifies the number of DAG (Direct Acyclic Graph) threads for MDS compactions with high priority. |
| ls_scale_out_factor |
|
The scaling-out factor of a log stream. This parameter specifies the number of log streams on each service node. |
| external_table_io_hole_size | V4.4.0 | Specifies the maximum distance (in bytes) between two consecutive I/O ranges. |
| external_table_io_range_size | V4.4.0 | Specifies the maximum size (in bytes) of a merge range. If the size of the merged range exceeds this value, the two consecutive ranges will not be merged. |
| async_ps_cursor_max_count | V4.4.0 | Specifies the maximum number of asynchronous PS cursors on a single node. |
| ob_enable_java_udf | V4.4.0 | Specifies whether to enable the Java UDF feature. |
| load_data_diagnosis_log_compression | V4.4.0 | Specifies the compression algorithm used for diagnostic logs. |
| load_data_diagnosis_log_max_size | V4.4.0 | Specifies the size of a single diagnostic log file. |
| result_cache_max_size | V4.4.0 | Specifies the maximum memory size that can be used by the result cache module. |
| result_cache_max_result | V4.4.0 | Specifies the maximum proportion of result_cache_max_size that can be used by a single result cache object. |
| ob_result_cache_evict_percentage | V4.4.0 | Used to set the memory eviction watermark for result cache. |
| ob_deterministic_udf_cache_max_size | V4.4.0 | Used to mark the maximum amount of memory that can be used for the cache pool of all deterministic UDFs during statement execution (in bytes). If set to 0, the execution cache feature is disabled. |
| attach_shared_sstable_thread_score | V4.4.0 | Used to configure the number of threads available to the tenant for executing shared data references in shared storage mode. |
| inc_sstable_upload_thread_score | V4.4.0 | Used to configure the number of threads available to the tenant for executing data sharing tasks in shared storage mode. |
| enable_lock_priority | V4.3.5 BP2 | Lock priority switch. |
| enable_adaptive_plan_cache | V4.3.5 BP2 | Used to control whether the tenant enables the adaptive plan cache (Plan Cache) feature. |
| global_index_auto_split_policy | V4.3.5 BP2 | Used to control whether to enable automatic partitioning for newly created global indexes.
NoticeStarting from V4.4.1, in the open-source edition, the default value of this parameter is changed to |
| default_storage_cache_policy | V4.3.5 BP2 | Used to configure the default cache strategy. |
| enable_manual_storage_cache_policy | V4.3.5 BP2 | Used to enable the user-specified hot cache strategy. |
| suspend_storage_cache_task | V4.3.5 BP2 | Used to set whether to suspend background cache tasks. |
| clog_io_isolation_mode | V4.3.5 BP2 | Used to determine whether to manage I/O requests on the clog disk based on whether the clog disk and data disk are independent. Users can adjust this parameter flexibly based on their system deployment to balance performance and resource utilization. |
| default_table_organization | V4.3.5 BP1 | Used to set the default table organization mode for tables. |
| px_node_policy | V4.3.5 BP1 | Used to determine the candidate pool for PX computing nodes. |
| ob_enable_java_env | V4.3.5 BP1 | Used to control whether to enable the Java environment required for external table capabilities such as HDFS/MaxCompute (ODPS). |
| ob_java_home | V4.3.5 BP1 | Used to set the Java home path required for JNI operations. This parameter must be configured after enabling the Java environment. |
| ob_java_opts | V4.3.5 BP1 | Used to set JVM startup options, such as memory size and garbage collection algorithm. This parameter must be configured after enabling the Java environment. |
| ob_java_connector_path | V4.3.5 BP1 | Used to set the path of the JAR package required for external table connectors. This parameter must be configured after enabling the Java environment. |
| temporary_file_max_disk_size | V4.3.5 BP1 | The maximum size of temporary files that can be occupied on a single node for a tenant. |
| package_state_sync_max_size | V4.3.5 BP1 | The maximum length of package variable values that can be synchronized. If the length exceeds the value specified for this parameter, the package variable will not be synchronized. |
| unit_gc_wait_time |
|
The maximum waiting time for Unit GC. If the maximum waiting time is exceeded, GC is forced. |
| recover_table_concurrency |
|
The maximum number of tables that can be restored in parallel during the cross-tenant table import phase of table-level recovery. |
| recover_table_dop |
|
The maximum number of tables that can be restored in parallel during the cross-tenant table import phase of table-level recovery. |
| query_memory_limit_percentage |
|
The percentage of tenant memory that can be used by a single SQL statement. |
| replica_parallel_migration_mode |
|
The mode for the parallel migration of log stream replicas. |
| sts_credential |
|
The credentials for accessing the STS service provided by OCP. |
| arbitration_degradation_policy | V4.3.4 | The strategy for automatic degradation. |
| kv_hbase_client_scanner_timeout_period | V4.3.4 | The timeout period for OBKV-HBase streaming queries. |
| default_load_mode | V4.3.4 | The hint to use when no hint is specified for a load operation. |
| direct_load_allow_fallback | V4.3.4 | Whether to report an error when direct load is not supported in a load operation. |
| enable_auto_split | V4.3.4 | Whether to enable the automatic partitioning feature for the table.
NoticeStarting from V4.4.1, for clusters created using the KV template, the default value of this parameter is changed to true. |
| auto_split_tablet_size | V4.3.4 | The threshold for triggering a split after the automatic partitioning feature is enabled for the tenant.
NoticeStarting from V4.4.1, the default value of this parameter is changed to 2 GB. |
| sync_io_thread_count | V4.3.4 | The number of threads for synchronous I/O requests. |
| ob_encoding_granularity | V4.3.3 | The maximum percentage of memory resources that can be used by the vector index module. |
| ob_storage_s3_url_encode_type | V4.3.3 | Specifies whether the URL encoding method used when sending requests to S3 is compatible with the RFC 3986 standard. |
| ob_vector_memory_limit_percentage | V4.3.3 | Specifies the threshold for memory resource usage of the vector index module (unit: percentage). |
| storage_rowsets_size | V4.3.2 | Controls the number of rows processed in one batch of vectorization by the columnar engine. |
| alert_log_level |
|
Specifies the level of warning logs. |
| enable_global_background_resource_isolation |
|
Controls whether to enable the global background resource isolation feature. |
| global_background_cpu_quota |
|
Controls the number of CPU cores for background tasks when global background resource isolation is enabled. |
| choose_migration_source_policy |
|
Specifies the priority strategy for selecting source replicas during migration. |
| lob_enable_block_cache_threshold |
|
Specifies the threshold for LOB query caching in OUTROW storage. |
| spill_compression_codec | V4.3.1 | Specifies the compression algorithm type for data disk-offloading compression during SQL execution. |
| max_partition_num |
|
Controls the maximum number of partitions allowed in MySQL-compatible mode. |
| log_storage_compress_all |
|
Controls whether to enable the clog storage compression feature. |
| syslog_compress_func |
|
Specifies the compression algorithm for system logs. |
| syslog_disk_size |
|
Specifies the maximum disk space for system logs. |
| syslog_file_uncompressed_count |
|
The number of system logs that are not compressed. |
| log_storage_compress_func |
|
The compression algorithm used for clog storage. |
| enable_dblink |
|
Whether to enable the DBLink feature. |
| data_disk_write_limit_percentage |
|
The percentage of the write limit for the data disk. |
| strict_check_os_params |
|
Whether to enable the OS configuration parameter check. |
| default_table_store_format | V4.3.0 | The default table storage format for user tenants. This parameter specifies the storage format for tables created in user tenants. Valid values: rowstore, columnstore, and rowstore_columnstore. |
| enable_rpc_authentication_bypass | V4.3.0 | In an OBServer cluster where RPC security authentication is enabled, specifies whether to allow the OMS migration service and OBKV service to bypass RPC security authentication to connect to the cluster. |
| sql_protocol_min_tls_version | V4.2.1 | The minimum SSL/TLS protocol version used for SSL connections to execute SQL statements. |
| compaction_dag_cnt_limit | V4.2.1 | The maximum number of DAGs in the Compaction DAG queue. |
| compaction_schedule_tablet_batch_cnt | V4.2.1 | The maximum number of partitions scheduled in each batch during Compaction. |
| enable_transfer | V4.2.1 | Whether to allow Transfer within a tenant. |
| ttl_thread_score | V4.2.1 | The number of threads used for TTL tasks. |
| local_ip | V4.2.0 | The IP address of the machine where the ObServer is installed. |
| observer_id | V4.2.0 | The unique identifier assigned to the OBServer node by the RS. |
| standby_fetch_log_bandwidth_limit | V4.2.0 | The maximum bandwidth that can be occupied by the total log synchronization traffic from all servers in the standby tenant cluster to the primary tenant cluster per second. |
| storage_meta_cache_priority | V4.2.0 | Controls the priority of storing Meta Cache in kvcache. |
| archive_lag_target | V4.2.0 | Controls the time for log archiving of a tenant. |
| log_disk_throttling_maximum_duration | V4.2.0 | Adjusts the maximum available time of the log disk after triggering log throttling. |
| log_disk_throttling_percentage | V4.2.0 | The percentage of unrecoverable log disk space that triggers log writing throttling. |
| ls_gc_delay_time | V4.2.0 | Configures the time for log stream delay deletion of a tenant. |
| partition_balance_schedule_interval | V4.2.0 | Sets the partition balancing scheduling cycle. |
| 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 | Sets the RPC timeout for log fetching from the standby database, to control the log transmission service to detect that a server in the primary database is unavailable and switch to another server. |
| standby_db_preferred_upstream_log_region | V4.1.0 | Configures the preferred region for a standby tenant to synchronize upstream logs. |
| log_storage_warning_tolerance_time | V4.1.0 | Sets the time from log disk I/O failure to disk being marked as bad. |
| ob_startup_mode | V4.1.0 | Sets the startup mode of an OBServer node, which can be modified only during the first startup. |
| sql_net_thread_count | V4.1.0 | Sets the number of MySQL cluster I/O threads, i.e., the number of global_sql_nio_server threads. |
| arbitration_timeout | V4.1.0 | Sets the timeout for triggering automatic downgrade. |
| dump_data_dictionary_to_log_interval | V4.1.0 | Controls the persistence cycle of the tenant data dictionary. |
| enable_user_defined_rewrite_rules | V4.1.0 | Controls whether to enable user-defined rules. |
| log_transport_compress_all | V4.1.0 | Specifies whether to use compression for log transmission. |
| log_transport_compress_func | V4.1.0 | Specifies the compression algorithm for log transmission. |
| rpc_memory_limit_percentage | V4.1.0 | Specifies the maximum percentage of the tenant memory that can be used for RPC. |
| tenant_sql_login_thread_count | V4.1.0 | Specifies the number of threads for MySQL-compatible tenant login, that is, the number of mysql_queue threads. |
| tenant_sql_net_thread_count | V4.1.0 | Specifies the number of I/O threads for MySQL-compatible tenants, that is, the number of sql_nio_server threads. |
| log_disk_percentage | V4.0.0 | Specifies the percentage of the total disk space that can be occupied by redo logs. |
| log_disk_size | V4.0.0 | Specifies the size of the redo log disk, that is, the total available space for the OBServer node. |
| ha_high_thread_score | V4.0.0 | Specifies the number of working threads for high-priority threads in high availability. |
| ha_low_thread_score | V4.0.0 | Specifies the number of working threads for low-priority threads in high availability. |
| ha_mid_thread_score | V4.0.0 | Specifies the number of working threads for medium-priority threads in high availability. |
| query_memory_limit_percentage |
|
Specifies the percentage of the tenant memory that can be used for a single SQL statement. |
Deprecated configuration items
The following table lists the configuration items that are deprecated in V4.x.
| Parameter Name | Description |
|---|---|
| global_write_halt_residual_memory | This parameter is no longer supported and has been removed since V4.2.0. |
| max_px_worker_count | This parameter is no longer supported and has been removed since V4.2.0. |
| plan_cache_high_watermark | This parameter is not supported and has been removed since V4.2.0. |
| plan_cache_low_watermark | This parameter is not supported and has been removed since V4.2.0. |
| rootservice_memory_limit | This parameter has been removed since V4.2.0 due to architecture changes. |
| system_trace_level | This parameter is no longer applicable and has been removed since V4.2.0 due to changes in the implementation logic. |
| token_reserved_percentage | This parameter is no longer applicable and has been removed since V4.2.0 due to changes in the implementation logic. |
| trace_log_sampling_interval | This parameter is no longer applicable and has been removed since V4.2.0 due to changes in the implementation logic. |
| io_category_config | This parameter is no longer applicable and has been removed since V4.2.0 due to changes in the implementation logic. |
| auto_broadcast_location_cache_rate_limit | This parameter has been removed since V4.0.0 due to architecture changes. |
| auto_leader_switch_interval | This parameter has been removed since V4.0.0 due to architecture changes. |
| auto_refresh_location_cache_rate_limit | This parameter has been removed since V4.0.0 due to architecture changes. |
| backup_backup_dest | This parameter is no longer supported and has been removed since V4.0.0. |
| backup_backup_dest_option | This parameter is no longer supported and has been removed since V4.0.0. |
| backup_dest_option | This parameter has been removed since V4.0.0 due to architecture changes. |
| backup_concurrency | This parameter is deprecated in V4.0.0. It is replaced by the ha_low_thread_score parameter added in V4.0.0. |
| backup_dest | This parameter is deprecated in V4.0.0. |
| backup_log_archive_option | This parameter is deprecated in V4.0.0. |
| backup_net_limit | This parameter is deprecated in V4.0.0. |
| backup_recovery_window | This parameter is deprecated in V4.0.0. |
| backup_region | This parameter is deprecated in V4.0.0. |
| backup_zone | This parameter is deprecated in V4.0.0. |
| balance_blacklist_failure_threshold | This parameter is deprecated in V4.0.0. |
| balance_blacklist_retry_interval | This parameter is deprecated in V4.0.0. |
| balancer_emergency_percentage | This parameter is deprecated in V4.0.0. |
| balancer_timeout_check_interval | This parameter is deprecated in V4.0.0. |
| clog_disk_utilization_threshold | This parameter is deprecated in V4.0.0. It is replaced by the log_disk_utilization_threshold parameter added in V4.0.0. |
| clog_expire_days | This parameter is deprecated in V4.0.0. |
| clog_cache_priority | This parameter is deprecated in V4.0.0. |
| clog_disk_usage_limit_percentage | This parameter is deprecated in V4.0.0. |
| clog_transport_compress_func | This parameter is not supported in V4.0.0 and is deprecated. It is replaced by the log_transport_compress_func parameter added in V4.1.0. |
| clog_max_unconfirmed_log_count | The feature is no longer supported and has been removed starting from V4.0.0. |
| clog_persistence_compress_func | The feature is no longer supported and has been removed starting from V4.0.0. It is supported again starting from V4.2.1 (excluding V4.3.0), and the new log_storage_compress_func configuration item has been introduced. |
| cpu_reserved | The feature has been removed starting from V4.0.0 due to architectural changes. |
| data_copy_concurrency | The feature has been removed starting from V4.0.0 due to logical changes. The new ha_high_thread_score configuration item has been introduced to replace this one. |
| default_transport_compress_func | The feature has been removed starting from V4.0.0 due to architectural changes. |
| election_cpu_quota | The feature has been removed starting from V4.0.0 due to architectural changes. |
| election_blacklist_interval | The feature has been removed starting from V4.0.0 due to architectural changes. |
| enable_auto_refresh_location_cache | The feature has been removed starting from V4.0.0 due to architectural changes. |
| enable_auto_leader_switch | The feature has been removed starting from V4.0.0 due to architectural changes. |
| enable_clog_persistence_compress | The feature is no longer supported and has been removed starting from V4.0.0. It is supported again starting from V4.2.1 (excluding V4.3.0), and the new log_storage_compress_all configuration item has been introduced. |
| enable_global_freeze_trigger | The feature has been removed starting from V4.0.0 due to architectural changes. |
| enable_log_archive | The feature has been removed starting from V4.0.0 due to architectural changes. |
| enable_election_group | The feature has been removed starting from V4.0.0 due to architectural changes. |
| enable_merge_by_turn | The feature is no longer supported and has been removed starting from V4.0.0. |
| enable_manual_merge | The feature is no longer supported and has been removed starting from V4.0.0. |
| enable_one_phase_commit | The feature is deprecated and will be removed in V4.0.0. |
| enable_pg | The feature is deprecated and will be removed in V4.0.0. |
| enable_separate_sys_clog | The feature is deprecated and will be removed in V4.0.0. |
| enable_smooth_leader_switch | The feature is deprecated and will be removed in V4.0.0. |
| enable_rootservice_standalone | The feature is deprecated and will be removed in V4.0.0. |
| fast_recovery_concurrency | The feature is deprecated and will be removed in V4.0.0. The new parameter ha_high_thread_score is added in V4.0.0. |
| flush_log_at_trx_commit | The feature is deprecated and will be removed in V4.0.0. |
| gc_wait_archive | The feature is deprecated and will be removed in V4.0.0. |
| global_index_build_single_replica_timeout | The feature is deprecated and will be removed in V4.0.0. |
| global_major_freeze_residual_memory | The feature is deprecated and will be removed in V4.0.0. |
| get_leader_candidate_rpc_timeout | The feature is deprecated and will be removed in V4.0.0. |
| ignore_replica_checksum_error | The feature is deprecated and will be removed in V4.0.0. |
| index_clog_cache_priority | The feature is deprecated and will be removed in V4.0.0. |
| index_info_block_cache_priority | The feature is deprecated and will be removed in V4.0.0. |
| index_cache_priority | The feature is deprecated and will be removed in V4.0.0. |
| ilog_index_expire_time | The feature is deprecated and will be removed in V4.0.0. |
| location_cache_priority | The feature is deprecated and will be removed in V4.0.0. |
| location_cache_expire_time | This parameter is removed starting from V4.0.0. |
| log_archive_batch_buffer_limit | This parameter is removed starting from V4.0.0. |
| log_archive_checkpoint_interval | This parameter is removed starting from V4.0.0. The parameter archive_lag_target is introduced in V4.0.0. |
| max_kept_major_version_number | This parameter is removed starting from V4.0.0. |
| merge_stat_sampling_ratio | This parameter is removed starting from V4.0.0. |
| merge_thread_count | This parameter is removed starting from V4.0.0. The parameter compaction_low_thread_score is introduced in V4.0.0. |
| merger_completion_percentage | This parameter is removed starting from V4.0.0. |
| merger_switch_leader_duration_time | This parameter is removed starting from V4.0.0. |
| merger_warm_up_duration_time | This parameter is removed starting from V4.0.0. |
| migrate_concurrency | This parameter is removed starting from V4.0.0. The parameter ha_mid_thread_score is introduced in V4.0.0. |
| minor_deferred_gc_time | This parameter is removed starting from V4.0.0. |
| minor_freeze_times | This parameter is removed starting from V4.0.0. The parameter major_compact_trigger is used instead. |
| minor_merge_concurrency | This parameter is removed starting from V4.0.0. The parameter compaction_mid_thread_score is introduced in V4.0.0. |
| minor_warm_up_duration_time | This parameter is removed starting from V4.0.0. |
| multiblock_read_gap_size | This parameter is removed starting from V4.0.0. |
| multiblock_read_size | The parameter is deprecated and removed starting from V4.0.0. |
| ob_esi_rpc_port | The parameter is deprecated and removed starting from V4.0.0. |
| enable_ob_esi_process | The parameter is deprecated and removed starting from V4.0.0. |
| ob_esi_session_timeout | The parameter is deprecated and removed starting from V4.0.0. |
| ob_esi_io_concurrency | The parameter is deprecated and removed starting from V4.0.0. |
| ob_esi_memory_limit | The parameter is deprecated and removed starting from V4.0.0. |
| ob_esi_syslog_level | The parameter is deprecated and removed starting from V4.0.0. |
| ob_esi_max_syslog_file_count | The parameter is deprecated and removed starting from V4.0.0. |
| ofs_list | The parameter is deprecated and removed starting from V4.0.0. |
| partition_table_check_interval | The parameter is deprecated and removed starting from V4.0.0. |
| rebuild_replica_data_lag_threshold | The parameter is deprecated and removed starting from V4.0.0. |
| replica_safe_remove_time | The parameter is deprecated and removed starting from V4.0.0. |
| resource_soft_limit | The parameter is deprecated and removed starting from V4.0.0. |
| restore_concurrency | The parameter is deprecated and removed starting from V4.0.0. The ha_high_thread_score parameter is added in V4.0.0 to replace this parameter. |
| row_purge_thread_count | The parameter is deprecated and removed starting from V4.0.0. |
| server_data_copy_out_concurrency | The parameter is deprecated and removed starting from V4.0.0. The ha_mid_thread_score parameter is added in V4.0.0 to replace this parameter. |
| server_data_copy_in_concurrency | The parameter is deprecated and will be removed in V4.0.0. The new parameter ha_mid_thread_score is introduced in V4.0.0 to replace this parameter. |
| sql_audit_memory_limit | The parameter is deprecated and will be removed in V4.0.0. The new variable ob_sql_audit_percentage is introduced in V4.0.0 to replace this parameter. |
| switchover_process_thread_count | The parameter is deprecated and will be removed in V4.0.0. |
| sys_bkgd_io_high_percentage | The parameter is deprecated and will be removed in V4.0.0. |
| sys_bkgd_io_low_percentage | The parameter is deprecated and will be removed in V4.0.0. |
| sys_cpu_limit_trigger | The parameter is deprecated and will be removed in V4.0.0. |
| system_cpu_quota | The parameter is deprecated and will be removed in V4.0.0. |
| tenant_groups | The parameter is deprecated and will be removed in V4.0.0. |
| trx_force_kill_threshold | The parameter is deprecated and will be removed in V4.0.0. |
| unit_balance_resource_weight | The parameter is deprecated and will be removed in V4.0.0. |
| user_iort_up_percentage | The parameter is deprecated and will be removed in V4.0.0. |
| user_tab_col_stat_cache_priority | The parameter is deprecated and will be removed in V4.0.0. |
| wait_leader_batch_count | The parameter is deprecated and will be removed in V4.0.0. |
| zone_merge_concurrency | The parameter is deprecated and will be removed in V4.0.0. |
| zone_merge_order | The parameter is deprecated and will be removed in V4.0.0. |
| zone_merge_timeout | The parameter is deprecated and will be removed in V4.0.0. |
Changes to system variables in V4.x
To better adapt to users' business scenarios, OceanBase Database has optimized and adjusted the default values and value ranges of tenant variables. Specifically, in previous versions, undo_retention was introduced as a system variable. However, starting from V4.0.0 in the V4.x series, undo_retention has been adjusted to be a tenant-level parameter.
System variables for changing default values
The following table lists the system variables for changing default values.
| Variable Name | Description |
|---|---|
| ob_default_lob_inrow_threshold |
|
| sql_mode |
|
| optimizer_features_enable |
|
| secure_file_priv | Starting from V4.2.1, the default value is changed from NULL to "". |
| max_allowed_packet | Starting from V4.2.1, the default value is changed from 4194304 to 16777216. |
| ob_max_read_stale_time | Starting from V4.1.0, the default value is changed from 5000000 to -1. |
| ob_trx_idle_timeout | Starting from V4.0.0, the default value is changed from 120s to 1d. |
| ob_trx_timeout | Starting from V4.0.0, the default value is changed from 100s to 1d. |
System variables for changing value ranges or meanings
The following table lists the system variables for changing value ranges or meanings.
| Variable Name | Description |
|---|---|
| secure_file_priv | Starting from V4.2.0, the meanings of the empty string ("") and NULL values are changed from "no restrictions" to "import and export are disabled". |
| ob_max_read_stale_time | Starting from V4.1.0, the value range is changed from [0, 9223372036854775807] to [-1, 9223372036854775807]. |
System variables for changing permission requirements
The following table lists the system variables for changing permission requirements.
| Variable Name | Description |
|---|---|
| secure_file_priv | Starting from V4.2.0, only local Unix Socket connections are allowed to modify this variable. |
New system variables
The following table lists the system variables introduced in V4.x.
| Variable name | Introduced in | 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 to parameterize anonymous blocks and call statements in PS mode 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 | Sets the number of 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 goals (such as LIMIT operators) during cardinality estimation. |
| pid_file |
|
Queries the path name of the file where the server writes its process ID. |
| port |
|
Sets the TCP/IP port number for the server to listen on when deploying an OBServer node. |
| socket |
|
Queries 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 preferred storage format when the optimizer generates plans for base tables. |
| cardinality_estimation_model |
|
Controls the correlation model used by the optimizer for row estimation. |
| activate_all_roles_on_login |
|
Controls whether to automatically enable all roles upon login. |
| innodb_stats_persistent |
|
Controls whether to persist InnoDB index statistics to disk. |
| ob_compatibility_control |
|
Controls the behavior mode when there are compatibility conflicts between MySQL 5.7 and MySQL 8.0. |
| ob_compatibility_version |
|
Controls the OceanBase Database version compatible with the feature that changes the product behavior. |
| ob_security_version |
|
The OceanBase Database version that is compatible with the security features. |
| automatic_sp_privileges |
|
Specifies whether to automatically grant the ALTER and EXECUTE privileges to stored procedures. |
| lc_time_names |
|
The language for displaying the names and abbreviations of dates and months. |
| ob_enable_pl_cache |
|
Specifies whether to enable the PL cache module. |
| optimizer_dynamic_sampling | V4.2.0 | The level of dynamic sampling. |
| optimizer_features_enable | V4.2.0 | Enables the optimizer features of different OceanBase Database versions. |
| parallel_degree_limit | V4.2.0 | The maximum degree of parallelism that the optimizer can choose when the Auto DOP strategy is used. |
| parallel_degree_policy | V4.2.0 | The strategy for selecting the degree of parallelism. |
| parallel_min_scan_time_threshold | V4.2.0 | The minimum estimated execution time for parallel processing of base table scans in the Auto DOP strategy. |
| runtime_filter_type | V4.2.0 | The type of Runtime Filter at the tenant level. |
| runtime_filter_wait_time_ms | V4.2.0 | The maximum wait time for a Runtime Filter. |
| runtime_filter_max_in_num | V4.2.0 | The number of distinct values (NDV) in a column for a Runtime In Filter. |
| runtime_bloom_filter_max_size | V4.2.0 | The maximum memory usage of a Runtime Bloom Filter, in bytes. |
| cte_max_recursion_depth | V4.1.0 | The maximum recursion depth of a common table expression (CTE). The server terminates the execution of any operation that exceeds this CTE value. |
| ob_max_read_stale_time | V4.1.0 | The maximum delay threshold (us) for weakly consistent reads. |
| regexp_stack_limit | V4.1.0 | The maximum available memory for the internal stack of a regular expression matching operation, in bytes by default. |
| ob_enable_show_trace | V4.1.0 | Specifies whether to use the Show Trace log. |
| cursor_sharing | V4.0.0 | Specifies whether to parameterize SQL statements. |
| innodb_strict_mode | V4.0.0 | Specifies the SQL syntax check mode. |
| log_row_value_options | V4.0.0 | Specifies whether to use partial updates for LOB data. |
| ob_enable_rich_error_msg | V4.0.0 | Specifies whether to display information such as svr_ip, time, and trace_id when an SQL statement execution error occurs. |
Deprecated system variables
The following table lists the system variables that are deprecated in V4.x.
| Variable | Description |
|---|---|
| ob_enable_trace_log | Deprecated in V4.1.0. |
| ob_create_table_strict_mode | Deprecated in V4.0.0. |
| ob_enable_blk_nestedloop_join | Removed in V4.0.0. |
| ob_enable_hash_group_by | Removed in V4.0.0. |
| ob_timestamp_service | Deprecated in V4.0.0. |