This topic describes cluster- and tenant-level parameters in OceanBase Database.
Cluster-level parameters
Bandwidth parameters
| Parameter | Description |
|---|---|
| enable_ob_ratelimit | Specifies whether to enable rate limiting between regions in a remote procedure call (RPC) connection. |
| ob_ratelimit_stat_period | The interval for calculating and updating the maximum bandwidth on OBServer nodes. |
Load balancing parameters
| Parameter | Description |
|---|---|
| balancer_idle_time | The interval for waking up the idle threads of backend tasks such as load balancing. |
| balancer_log_interval | The interval for printing statistical logs generated by the threads of backend tasks such as load balancing. |
| balancer_timeout_check_interval | The interval for checking whether backend tasks such as load balancing time out. |
| balancer_task_timeout | The timeout period of backend tasks such as load balancing. |
| balancer_tolerance_percentage | The tolerance for disk imbalance among multiple units of a tenant, which is set in the load balancing strategy. If the imbalance is within the range that starts at the average value minus the tolerance and ends at the average value plus the tolerance, no balancing action is triggered. |
| balancer_emergency_percentage | The load threshold of each unit. When the load of a unit exceeds the specified threshold, you can enable replica migration to an external system for load balancing even during a major compaction. |
| enable_rebalance | Specifies whether to enable automatic load balancing. |
| server_balance_critical_disk_waterlevel | The disk usage threshold that triggers disk load balancing. |
| server_balance_disk_tolerance_percent | The tolerance for disk load imbalance among nodes, which is set in the load balancing strategy. |
| tenant_groups | The tenant groups used in the load balancing strategy. |
| resource_hard_limit | Specifies how resource units are allocated. |
| resource_soft_limit | Specifies whether to enable unit balancing. |
| unit_balance_resource_weight | The resource weight used in the unit balancing strategy. Generally, you do not need to set this parameter. |
| enable_sys_unit_standalone | Specifies whether the unit of the sys tenant exclusively occupies a node. |
Replica parameters
| Parameter | Description |
|---|---|
| balance_blacklist_failure_threshold | The maximum number of consecutive failures of a backend task such as replica migration. |
| balance_blacklist_retry_interval | The retry interval for a backend task such as replica migration that is added to the blocklist. |
| enable_rereplication | Specifies whether to enable automatic data synchronization to replicas. |
| global_index_build_single_replica_timeout | The timeout period for creating a replica during global index creation. |
| ignore_replica_checksum_error | Specifies whether to ignore the checksum errors of replicas. |
| replica_safe_remove_time | The retention period of a deleted replica before it can be cleared. |
| sys_bkgd_migration_change_member_list_timeout | The timeout period for modifying the Paxos member list during replica migration. |
| sys_bkgd_migration_retry_num | The maximum number of retries after a replica migration task fails. |
| enable_smooth_leader_switch | Specifies whether to enable smooth leader switchover. |
| election_blacklist_interval | The interval during which the dismissed leader cannot be re-elected as the leader. |
| enable_auto_leader_switch | Specifies whether to enable automatic leader switchover. |
| get_leader_candidate_rpc_timeout | The timeout period of an internal request for obtaining the leader candidate in the automatic leader switchover strategy. |
| rebuild_replica_data_lag_threshold | The threshold of the size difference of transaction logs between the leader and a follower. When the difference reaches the threshold, replica reconstruction is triggered. |
Backup and restore parameters
| Parameter | Description |
|---|---|
| enable_log_archive | Specifies whether to enable log archiving. |
| backup_dest_option | The parameters for backup. |
| backup_backup_dest_option | The parameters for second backup. |
| backup_log_archive_option | The options for log archiving during backup. |
| backup_zone | The zone for which backup tasks are run. |
| log_archive_checkpoint_interval | The interval between log archiving checkpoints of cold data. |
| log_archive_concurrency | The concurrency of log archiving. |
| log_archive_batch_buffer_limit | The maximum memory available for log archiving on a single server when physical backup is enabled. |
| log_restore_concurrency | The concurrency of log restoration. |
| auto_delete_expired_backup | Specifies whether to enable automatic deletion of expired backups. |
| backup_concurrency | The concurrency of data writes to the file system during backup. |
| backup_dest | The path for baseline data backup and log archiving. |
| backup_net_limit | The total bandwidth for cluster backup. |
| backup_recovery_window | The time window in which backups can be recovered. |
| backup_region | The region for which backup tasks are run. |
| restore_concurrency | The maximum concurrency of tenant data restore from backups. |
| backup_backup_dest | The destination for second backup. |
| backup_backup_archive_log_batch_count | The number of batches of tasks for secondary log backup. |
| backup_backup_archivelog_retry_interval | The interval for retrying tasks for secondary log backup. |
| backup_backupset_batch_count | The number of batches of tasks for secondary baseline data backup. |
| backup_backupset_retry_interval | The interval for retrying tasks for secondary baseline data backup. |
Primary and standby cluster parameters
| Parameter | Description |
|---|---|
| switchover_process_thread_count | The size of the thread pool for primary/standby cluster switchover. |
Cluster parameters
| Parameter | Description |
|---|---|
| cluster | The name of the current OceanBase cluster. |
| cluster_id | The ID of the current OceanBase cluster. |
| rpc_timeout | The timeout period of an internal request in the cluster. |
SQL parameters
| Parameter | Description |
|---|---|
| sql_login_thread_count | The number of threads for processing SQL logon requests. |
External storage API parameters
| Parameter | Description |
|---|---|
| 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 process (external storage API). |
| ob_esi_session_timeout | The timeout period of the active session resources for the obesi process. |
| ob_esi_io_concurrency | The I/O concurrency for the obesi process. |
| ob_esi_memory_limit | The maximum memory size for the obesi process. |
| ob_esi_syslog_level | The current log level for the obesi process. |
| ob_esi_max_syslog_file_count | The maximum number of log files that can be retained for the obesi process. |
CPU parameters
| Parameter | Description |
|---|---|
| cpu_count | The total number of CPUs in the system. If the parameter is set to 0, the system will automatically detect the number of CPUs. |
| cpu_quota_concurrency | The maximum concurrency allowed for each CPU quota of a tenant. |
| cpu_reserved | The number of CPUs reserved in the system. The remaining CPUs are exclusively occupied by OceanBase Database. |
| election_cpu_quota | The CPU quota allocated to backend tasks related to replica election. |
| server_balance_cpu_mem_tolerance_percent | The tolerance of CPU and memory resource imbalance in the node load balancing strategy. |
| server_cpu_quota_max | The maximum CPU quota for the system. |
| server_cpu_quota_min | The minimum CPU quota for the system. The system automatically reserves the quota. |
| system_cpu_quota | The CPU quota for the SYS tenant. |
| sys_cpu_limit_trigger | The CPU utilization threshold. When CPU utilization reaches the threshold, backend tasks in the system will be suspended. |
| token_reserved_percentage | The percentage of idle tokens reserved for tenants in the scheduling of CPUs for the tenants. |
| workers_per_cpu_quota | The number of worker threads allocated to each CPU quota. |
Directory parameters
| Parameter | Description |
|---|---|
| config_additional_dir | The local directories for storing multiple copies of configuration files for redundancy. |
| data_dir | The directory for storing SSTables and other data. |
Memory parameters
| Parameter | Description |
|---|---|
| datafile_disk_percentage | The percentage of used space to the total space of the disk where the data_dir directory is located. This disk will be initialized for data storage by the OceanBase Database system. |
| data_disk_usage_limit_percentage | The percentage of data write space to the total space of the disk. When the data write space reaches the threshold, data can no longer be written to the disk. |
| enable_sql_operator_dump | Specifies whether to allow intermediate SQL processing results to be written to the disk to release the memory. |
| global_write_halt_residual_memory | The global available memory threshold that triggers the suspension of write operations of user tenants. (The sys tenant is not affected.) |
| leak_mod_to_check | The internal debugging feature used for memory leakage check. |
| memory_chunk_cache_size | The total cache size of the memory allocator. |
| memory_limit | The total size of available memory. |
| memory_limit_percentage | The percentage of available memory to total memory in the system. |
| memory_reserved | The memory size reserved by the system for the KV cache. |
| memstore_limit_percentage | The percentage of the memory that can be occupied by the MemStore to the total available memory of a tenant. |
| system_memory | The memory size reserved by the system for the SYS500 tenant. |
| sql_audit_memory_limit | The maximum memory available for SQL audit data. |
| use_large_pages | Manages the use of large memory pages by the database. |
Debugging parameters
| Parameter | Description |
|---|---|
| debug_sync_timeout | The timeout period for a Debug Sync operation. When the value is set to 0, Debug Sync is disabled. |
| enable_rich_error_msg | Specifies whether to add debugging information, such as the server address, error time, and trace ID, to the client message. |
Compression algorithm parameters
| Parameter | Description |
|---|---|
| default_compress_func | The default algorithm for compressing table data. You can also specify another compression algorithm when creating a table. |
| default_compress | The default compression strategy used during table creation in Oracle mode. |
| tableapi_transport_compress_func | The algorithm for compressing TableAPI query results for transmission. |
| default_transport_compress_func | The RPC compression algorithm used for the entire cluster. |
Transaction and transaction log parameters
| Parameter | Description |
|---|---|
| trx_try_wait_lock_timeout | The maximum amount of time that a statement waits for a locked row to be unlocked. |
| trx_force_kill_threshold | The maximum amount of time that the system waits before killing a transaction due to a freeze or leader switchover. |
| clog_cache_priority | The caching priority of transaction logs. |
| clog_sync_time_warn_threshold | The warning threshold of time consumed for synchronizing transaction logs. When the consumed time reaches the threshold, a WARN-level log is generated. |
| clog_disk_usage_limit_percentage | The maximum percentage of I/O usage of the transaction log disk. |
| clog_transport_compress_all | Specifies whether to compress transaction logs for transmission. |
| clog_transport_compress_func | The algorithm for compressing transaction logs for internal transmission. |
| dtl_buffer_size | The size of the cache allocated to the SQL data transmission module. |
| enable_one_phase_commit | Specifies whether to enable one-phase commit. |
| ignore_replay_checksum_error | Specifies whether to ignore checksum errors that occur during transaction log playback. |
| trx_2pc_retry_interval | The interval for retrying a failed two-phase commit task. |
| clog_disk_utilization_threshold | The usage of the clog or ilog disk space that triggers log file reuse. |
| index_clog_cache_priority | The priority of the transaction log index in the cache system. |
| clog_expire_days | The retention period of clog files. When the retention period of a clog file expires, it will be deleted. |
| gc_wait_archive | Specifies whether to start garbage collection for a partition until all the logs in the partition have been archived. |
Minor and major compaction parameters
| Parameter | Description |
|---|---|
| enable_global_freeze_trigger | Specifies whether to enable automatic triggering of a global freeze. |
| enable_manual_merge | Specifies whether to enable manual major compaction. |
| enable_merge_by_turn | Specifies whether to enable the rotating major compaction strategy. |
| enable_major_freeze | Specifies whether to enable automatic global freezing. |
| freeze_trigger_percentage | The threshold of memory used by tenants for triggering a global freeze. |
| global_major_freeze_residual_memory | The threshold of remaining memory for triggering a global freeze. |
| major_freeze_duty_time | The time to trigger a freeze and a major compaction every day. |
| max_kept_major_version_number | The number of frozen data versions to be retained. |
| merge_stat_sampling_ratio | The sampling rate of data column statistics in a major compaction. |
| major_compact_trigger | The number of minor compactions for triggering a global major compaction. |
| merge_thread_count | The number of worker threads for daily major compactions. |
| merger_check_interval | The interval for scheduling the thread for checking the major compaction status. |
| merger_completion_percentage | The percentage of compacted replicas at which the major compaction task is considered completed. |
| merger_switch_leader_duration_time | The interval for a batch leader switchover in a daily major compaction. |
| merger_warm_up_duration_time | The preload time of new baseline data in a major compaction. |
| minor_compact_trigger | The threshold for triggering the next-level compaction in hierarchical minor compactions. |
| minor_deferred_gc_time | The interval between the time when garbage collection starts for SSTables and the time when the major compaction ends. |
| minor_freeze_times | The number of minor compactions for triggering a global major compaction. |
| minor_warm_up_duration_time | The preload time of the new MemTable generated after a minor compaction. |
| minor_merge_concurrency | The number of concurrent threads in a minor compaction. |
| micro_block_merge_verify_level | The verification level of macroblocks in a major compaction. |
| row_compaction_update_limit | The number of data updates that triggers a major compaction of rows in the memory. |
| row_purge_thread_count | The maximum number of worker threads for a major compaction of rows in the memory. |
| zone_merge_concurrency | The number of zones supported in a major compaction. |
| zone_merge_order | The order of zones in a rotating major compaction. |
| zone_merge_timeout | The timeout period for the major compaction of a zone. |
PX parameters
| Parameter | Description |
|---|---|
| px_workers_per_cpu_quota | The ratio of Parallel eXecution (PX) worker threads. |
| px_task_size | The amount of data processed by the SQL parallel query engine in each task. |
| max_px_worker_count | The maximum number of threads for the SQL parallel query engine. |
Cache parameters
| Parameter | Description |
|---|---|
| bf_cache_miss_count_threshold | The number of macroblock misses that triggers the creation of the Bloom filter cache. |
| bf_cache_priority | The priority of the Bloom filter cache. |
| cache_wash_threshold | The remaining capacity threshold that triggers cache cleanup. |
| fuse_row_cache_priority | The priority of the fuse row cache in the cache system. |
| multiblock_read_gap_size | The size of multiple block caches from which data can be read in one I/O operation. |
| user_row_cache_priority | The priority of the baseline data row cache in the cache system. |
| user_tab_col_stat_cache_priority | The priority of the statistics cache in the cache system. |
| index_cache_priority | The priority of the index cache in the cache system. |
| index_info_block_cache_priority | The priority of the block index in the cache system. |
| autoinc_cache_refresh_interval | The refresh interval for the auto-increment column cache. |
| plan_cache_evict_interval | The eviction interval for the execution plan cache. |
| enable_auto_refresh_location_cache | Specifies whether to enable automatic refresh of the location cache. |
| auto_refresh_location_cache_rate_limit | The maximum number of partitions that can be automatically refreshed on each OBServer node at a time. |
| auto_broadcast_location_cache_rate_limit | The maximum number of partitions whose location changes can be broadcast on each OBServer node per second. |
| user_block_cache_priority | The priority of the data block cache in the cache system. |
Location cache parameters
| Parameter | Description |
|---|---|
| virtual_table_location_cache_expire_time | The validity period of the location cache of the virtual table. |
| location_cache_refresh_rpc_timeout | The timeout period for refreshing the location cache through RPC. |
| location_cache_refresh_sql_timeout | The timeout period for refreshing the location cache through SQL. |
| force_refresh_location_cache_interval | The maximum interval for refreshing the location cache. |
| force_refresh_location_cache_threshold | The maximum number of times that the location cache is refreshed per second. Throttling is performed if this threshold is exceeded. |
| location_cache_priority | The priority of the location cache in the cache system. |
| location_cache_refresh_min_interval | The minimum interval for sending location cache refresh requests, which prevents excessive refresh requests from overloading the system. |
| location_cache_cpu_quota | The CPU quota for the location cache module. |
| location_fetch_concurrency | The maximum number of concurrent requests for refreshing the location cache on a single server. |
| location_cache_expire_time | The validity period of partition location information in the partition location cache. We recommend that you do not modify this parameter. |
| location_refresh_thread_count | The number of threads used by OBServer node to obtain partition location information from RootService. |
Log parameters
| Parameter | Description |
|---|---|
| enable_record_trace_log | Specifies whether to record trace logs. |
| enable_async_syslog | Specifies whether to enable asynchronous writing of system logs. |
| enable_syslog_recycle | Specifies whether to enable recycling for system logs. |
| enable_syslog_wf | Specifies whether to print system logs above the WARN level to a separate log file. |
| enable_separate_sys_clog | Specifies whether to separately store system transaction logs and user transaction logs. |
| flush_log_at_trx_commit | The transaction log write strategy adopted when transactions are committed. |
| max_string_print_length | The maximum length of a single row when system logs are printed. |
| max_syslog_file_count | The maximum number of log files that can be retained. |
| syslog_level | The level of system logs. |
| trace_log_sampling_interval | The interval at which trace logs are printed. |
| ilog_index_expire_time | The validity period of ilog files on OBServer nodes. Expired files can no longer be read. |
| diag_syslog_per_error_limit | The number of DIAG system logs allowed for each error code per second. When this threshold is reached, no more logs will be printed. |
Partition parameters
| Parameter | Description |
|---|---|
| enable_pg | Specifies whether to enable the partition group feature. |
| partition_table_check_interval | The interval at which the OBServer node deletes non-existent replicas from a partitioned table. |
| partition_table_scan_batch_count | The number of records in a partitioned table that can be read in a batch. |
| tablet_size | The size of each shard during intra-partition parallel processing such as parallel compactions and queries. |
Read/write and query parameters
| Parameter | Description |
|---|---|
| weak_read_version_refresh_interval | The version refresh interval for weak consistency reads. This parameter affects the latency of weak consistency reads. |
| large_query_worker_percentage | The percentage of worker threads reserved for large queries. |
| large_query_threshold | The execution time threshold to identify a large query. |
| trace_log_slow_query_watermark | The execution time threshold to identify a slow query. Trace logs of slow queries are written to system logs. |
RootService parameters
| Parameter | Description |
|---|---|
| auto_leader_switch_interval | The working interval of the backend thread for automatic leader switchover. |
| rootservice_async_task_queue_size | The size of the internal asynchronous task queue for RootService. |
| rootservice_async_task_thread_count | The size of the thread pool for internal asynchronous tasks of RootService. |
| rootservice_list | The servers on which RootService and its replicas run. |
| rootservice_ready_check_interval | The wait time after RootService is started, during which the cluster status is checked. |
| rootservice_memory_limit | The maximum memory available to RootService. |
| wait_leader_batch_count | The maximum number of partitions to which RootService can send a command for leader switchover. |
| enable_rootservice_standalone | Specifies whether to allow the SYS tenant and RootService to exclusively occupy an OBServer node. |
| lease_time | The heartbeat lease period. |
| server_check_interval | The interval at which the server checks the table consistency. |
| server_permanent_offline_time | The time threshold for heartbeat missing at which a server is considered permanently offline. Data replicas on a permanently offline server must be automatically supplemented. |
| ob_event_history_recycle_interval | The interval at which historical events are recycled. |
Concurrency parameters
| Parameter | Description |
|---|---|
| server_data_copy_in_concurrency | The maximum concurrency for data migration to a single node. |
| server_data_copy_out_concurrency | The maximum concurrency for data migration from a single node. |
| fast_recovery_concurrency | The maximum concurrency for executing fast restore tasks scheduled by RootService on an OBServer node. |
| data_copy_concurrency | The maximum concurrency for data migration and replication in the system. |
| migrate_concurrency | The maximum concurrency for internal data migration. |
I/O parameters
| Parameter | Description |
|---|---|
| sys_bkgd_io_high_percentage | The highest percentage of disk bandwidth that can be used by backend I/O operations. |
| sys_bkgd_io_low_percentage | The lowest percentage of traffic for backend I/O operations. |
| syslog_io_bandwidth_limit | The maximum I/O bandwidth available for system logs. If this value is reached, the remaining system logs are discarded. |
| user_iort_up_percentage | The I/O latency threshold for the user disk. When the I/O latency of the user disk reaches this threshold, the traffic of backend I/O operations will be throttled. |
| disk_io_thread_count | The number of disk I/O threads. The value must be an even number. |
| multiblock_read_size | The I/O aggregate throughput in data access. |
| net_thread_count | The number of network I/O threads. |
TCP parameters
| Parameter | Description |
|---|---|
| enable_tcp_keepalive | Specifies whether to enable the keepalive mechanism for client connections. |
| tcp_keepidle | The interval in seconds before sending a keepalive probe packet when no data is sent on a client connection. |
| tcp_keepintvl | The interval between two probes in seconds when you enable the keepalive mechanism for client connections. |
| tcp_keepcnt | The maximum number of retries before terminating a non-active connection. |
RPC security parameters
| Parameter | Description |
|---|---|
| rpc_client_authentication_method | The security authentication method for the RPC client. |
| rpc_server_authentication_method | The security authentication method for the RPC server. |
Other parameters
| Parameter | Description |
|---|---|
| all_cluster_list | The list of servers that access the same URL specified for config_url. |
| builtin_db_data_verify_cycle | The cycle of a bad block check in the unit of days. When the value is set to 0, the bad block check is not performed. |
| data_storage_warning_tolerance_time | The tolerance period after which the data disk is set to the WARNING state. |
| dead_socket_detection_timeout | The interval for detecting invalid sockets. |
| internal_sql_execute_timeout | The interval of DML requests in the system. |
| migration_disable_time | The period during which data migration is suspended for a node after data migration to the node fails due to reasons such as full disk usage. |
| schema_history_expire_time | The validity period of history metadata. |
| ofs_list | The list of URLs for connecting to the OceanBase File System (OFS) of all the zones so that RootService can access files across zones in OFS deployment mode. OFS is a distributed storage system independently designed for OceanBase Database. |
| datafile_size | The size of a data file. This parameter is generally left unspecified. |
| devname | The name of the network interface card (NIC) to which the service process is bound. |
| enable_perf_event | Specifies whether to enable the information collection feature for performance events. |
| enable_record_trace_id | Specifies whether to record the trace ID configured by the application. |
| enable_upgrade_mode | Specifies whether to enable the upgrade mode. In upgrade mode, some backend system features are suspended. |
| enable_ddl | Specifies whether to allow the execution of DDL statements. |
| high_priority_net_thread_count | The number of network threads with a high priority. When this parameter is set to 0, this feature is disabled. |
| mysql_port | The port number for the SQL service protocol. |
| obconfig_url | The URL of the OBConfig service. |
| rpc_port | The RPC port. |
| ssl_client_authentication | Specifies whether to enable SSL authentication. |
| stack_size | The size of the function call stack for programs. |
| tenant_task_queue_size | The request queue size of each tenant. |
| zone | The name of the zone where the node is located. This parameter is generally left unspecified. |
| ssl_external_kms_info | The information that the SSL feature of OceanBase Database relies on, which is recorded in JSON strings for different SSL modes. Such a JSON string contains at least the ssl_mode field. |
| recyclebin_object_expire_time | The period during which a schema object can be retained in the recycle bin. After the period elapses, the object will be purged from the recycle bin. |
| default_row_format | The default row format used in table creation in MySQL mode. |
| enable_election_group | Specifies whether to enable the election group strategy. |
| enable_sql_audit | Specifies whether to enable SQL audit. |
| min_observer_version | The earliest OBServer version in the cluster. |
| sys_bkgd_net_percentage | The maximum percentage of network bandwidth for backend system tasks. |
| schema_history_recycle_interval | The interval for recycling schema multi-version history files. |
Unsupported parameters
| Parameter | Description |
|---|---|
| all_cluster_list | The list of servers that access the same URL specified for config_url. |
| enable_unit_balance_resource_weight | Specifies whether to enable manual configuration of resource weights. |
| plan_cache_high_watermark | The memory threshold to trigger plan cache eviction. Automatic eviction is triggered when the memory occupied by the plan cache reaches the specified threshold. |
| plan_cache_low_watermark | The memory threshold to stop plan cache eviction. The eviction is stopped when the memory occupied by the plan cache decreases to the specified threshold. |
| server_temporary_offline_time | The time threshold for heartbeat missing at which a server is considered temporarily offline. |
| sql_audit_queue_size | The maximum number of records of SQL audit data allowed. |
| tenant_cpu_variation_per_server | The variation allowed for CPU quota scheduling among multiple units of a tenant. |
| system_trace_level | The level of system trace logs to be printed. |
Tenant-level parameters
User logon parameters
Note
The following table describes the parameters that take effect only in MySQL mode.
| Parameter | Description |
|---|---|
| connection_control_failed_connections_threshold | The threshold of failed logon attempts. |
| connection_control_min_connection_delay | The minimum lock period for an account whose number of failed logon attempts reaches the specified threshold. |
| connection_control_max_connection_delay | The maximum lock period for an account whose number of failed logon attempts reaches the specified threshold. |
Audit parameters
| Parameter | Description |
|---|---|
| audit_sys_operations | Specifies whether to track the operations of the SYS user. |
| audit_trail | Specifies whether to enable database audit. |
Transaction and transaction log parameters
| Parameter | Description |
|---|---|
| writing_throttling_maximum_duration | The time required for allocating the remaining memory of the MemStore after the write speed is limited. This parameter controls the write speed by controlling the memory allocation progress. |
| writing_throttling_trigger_percentage | The upper limit of the write speed. |
| clog_persistence_compress_func | The algorithm for compressing transaction logs for storage. |
| clog_max_unconfirmed_log_count | The maximum number of unconfirmed logs allowed in the transaction module. |
| enable_clog_persistence_compress | Specifies whether to compress transaction logs for storage. |
Minor and major compaction parameters
| Parameter | Description |
|---|---|
| default_progressive_merge_num | The default number of progressive major compactions during table creation. |
Encryption parameters
| Parameter | Description |
|---|---|
| external_kms_info | The key management information. |
| tde_method | The encryption method for a transparent tablespace. |
PL parameters
| Parameter | Description |
|---|---|
| plsql_ccflags | The compilation constants of the PL compiler. |
| plsql_code_type | The compilation mode of PL/SQL code. |
| plsql_debug | Specifies whether to compile code for debugging. |
| plsql_optimize_level | The compilation optimization level. |
| plsql_v2_compatibility | Specifies whether compatibility with Oracle 8 is supported. This parameter applies only to the Oracle mode and does not take effect now. |
| plsql_warnings | Controls the error reporting behavior of the PL/SQL compiler. You can use this parameter to specify the status of a warning code or a warning code type to enable, disable, or error. |
Compatibility parameters
Note
The following table describes the parameters that take effect only in MySQL mode.
| Parameter | Description |
|---|---|
| enable_sql_extension | Specifies whether to enable SQL extension for tenants. |
Read/write and query parameters
| Parameter | Description |
|---|---|
| enable_monotonic_weak_read | Specifies whether to enable monotonic reads. |
| max_stale_time_for_weak_consistency | The maximum latency allowed in weak consistency reads. |
Routing parameters
| Parameter | Description |
|---|---|
| ob_proxy_readonly_transaction_routing_policy | Specifies whether ODP routes a transaction based on read-only statements. |
Other parameters
| Parameter | Description |
|---|---|
| enable_early_lock_release | Specifies whether to enable the early lock release (ELR) feature. |
| workarea_size_policy | Specifies whether the size of an SQL workarea is manually or automatically adjusted. |
| open_cursors | The maximum number of cursors that can be concurrently opened in a single session. |
| ob_ssl_invited_common_names | The list of identities of applications running under the current tenant. The identity of an application comes from the cn (common name) field of the subject of the client certificate in two-way SSL authentication. |
| ob_enable_batched_multi_statement | Specifies whether to enable group-based execution optimization for the batch processing feature. |
| job_queue_processes | The maximum number of concurrent tasks that can be run under each tenant. You can set this parameter to prevent tenant resources from being excessively occupied by tasks. Note This parameter takes effect only in Oracle mode. |
| ob_query_switch_leader_retry_timeout | The maximum retry period for failed queries, in us. |
Unsupported parameters
| Parameter | Description |
|---|---|
| sql_work_area | The workarea memory of a tenant. |