MySQL 5.6 Reference Manual Including MySQL NDB Cluster 7.3-7.4 Reference Guide

18.1.5.1 Options, Variables, and Parameters Added, Deprecated or Removed in NDB 7.3

The next few sections contain information about NDB node configuration parameters and NDB-specific mysqld options and variables that have been added to, deprecated in, or removed from NDB 7.3.

Parameters Introduced in NDB 7.3

The following node configuration parameters have been added in NDB 7.3.

  • ConnectBackoffMaxTime: Specifies longest time in milliseconds (~100ms resolution) to allow between connection attempts to any given data node by this API node. Excludes time elapsed while connection attempts are ongoing, which in worst case can take several seconds. Disable by setting to 0. If no data nodes are currently connected to this API node, StartConnectBackoffMaxTime is used instead. Added in NDB 7.3.7.

  • DiskPageBufferEntries: Memory to allocate in DiskPageBufferMemory; very large disk transactions may require increasing this value. Added in NDB 7.3.8.

  • HeartbeatIntervalMgmdMgmd: Time between management-node-to-management-node heartbeats; connection between management nodes is considered lost after 3 missed heartbeats. Added in NDB 7.3.3.

  • LcpScanProgressTimeout: Maximum time that local checkpoint fragment scan can be stalled before node is shut down to ensure systemwide LCP progress. Use 0 to disable. Added in NDB 7.3.3.

  • RestartSubscriberConnectTimeout: Amount of time for data node to wait for subscribing API nodes to connect. Set to 0 to disable timeout, which is always resolved to nearest full second. Added in NDB 7.3.6.

  • StartConnectBackoffMaxTime: Same as ConnectBackoffMaxTime except that this parameter is used in its place if no data nodes are connected to this API node. Added in NDB 7.3.7.

  • TimeBetweenGlobalCheckpointsTimeout: Minimum timeout for group commit of transactions to disk. Added in NDB 7.3.9.

Parameters Deprecated in NDB 7.3

The following node configuration parameters have been deprecated in NDB 7.3.

Parameters Removed in NDB 7.3

No node configuration parameters have been removed in NDB 7.3.

Options and Variables Introduced in NDB 7.3

The following system variables, status variables, and server options have been added in NDB 7.3.

  • Ndb_last_commit_epoch_server: Epoch most recently committed by NDB. Added in NDB 7.3.8.

  • Ndb_last_commit_epoch_session: Epoch most recently committed by this NDB client. Added in NDB 7.3.8.

  • Ndb_slave_max_replicated_epoch: Most recently committed NDB epoch on this replica. When this value is greater than or equal to Ndb_conflict_last_conflict_epoch, no conflicts have yet been detected. Added in NDB 7.3.8.

  • create_old_temporals: Use pre-5.6.4 storage format for temporal types when creating tables. Intended for use in replication and upgrades/downgrades between NDB 7.2 and NDB 7.3/7.4. Added in NDB 7.3.10.

  • ndb_eventbuffer_max_alloc: Maximum memory that can be allocated for buffering events by NDB API. Defaults to 0 (no limit). Added in NDB 7.3.3.

  • ndb_recv_thread_activation_threshold: Activation threshold when receive thread takes over polling of cluster connection (measured in concurrently active threads). Added in NDB 7.3.1.

  • ndb_recv_thread_cpu_mask: CPU mask for locking receiver threads to specific CPUs; specified as hexadecimal. See documentation for details. Added in NDB 7.3.1.

  • ndb_show_foreign_key_mock_tables: Show mock tables used to support foreign_key_checks=0. Added in NDB 7.3.2.

Options and Variables Deprecated in NDB 7.3

The following system variables, status variables, and options have been deprecated in NDB 7.3.

  • create_old_temporals: Use pre-5.6.4 storage format for temporal types when creating tables. Intended for use in replication and upgrades/downgrades between NDB 7.2 and NDB 7.3/7.4. Deprecated as of NDB 7.3.10.

Options and Variables Removed in NDB 7.3

The following system variables, status variables, and options have been removed in NDB 7.3.

  • ndb_index_stat_cache_entries: Granularity of statistics by determining number of starting and ending keys. Removed in NDB 7.3.5.

  • ndb_index_stat_update_freq: How often to query data nodes rather than statistics cache. Removed in NDB 7.3.5.