14.18.1.3 Functions to Inspect and Configure the Maximum Consensus Instances of a Group

The following functions enable you to inspect and configure the maximum number of consensus instances that a group can execute in parallel.

• group_replication_get_write_concurrency()

  Check the maximum number of consensus instances that a group can execute in parallel.

  Syntax:

  INT group_replication_get_write_concurrency()

  This function has no parameters.

  Return value:

  The maximum number of consensus instances currently set for the group.

  Example:

  SELECT group_replication_get_write_concurrency()

  For more information, see Section 20.5.1.3, “Using Group Replication Group Write Consensus”.

• group_replication_set_write_concurrency()

  Configures the maximum number of consensus instances that a group can execute in parallel. The GROUP_REPLICATION_ADMIN privilege is required to use this function.

  Syntax:

  STRING group_replication_set_write_concurrency(instances)

  Arguments:

  • members: Sets the maximum number of consensus instances that a group can execute in parallel. Default value is 10, valid values are integers in the range of 10 to 200.

  Return value:

  Any resulting error as a string.

  Example:

  SELECT group_replication_set_write_concurrency(instances);

  For more information, see Section 20.5.1.3, “Using Group Replication Group Write Consensus”.