17.3 Monitoring Group Replication

Use the Perfomance Schema tables to monitor Group Replication, assuming that the Performance Schema is enabled. Group Replication adds the following tables:

These Perfomance Schema replication tables also show information about Group Replication:

  • performance_schema.replication_connection_status shows information regarding Group Replication, for example the transactions that have been received from the group and queued in the applier queue (the relay log).

  • performance_schema.replication_applier_status shows the state of the Group Replication related channels and threads If there are many different worker threads applying transactions, then the worker tables can also be used to monitor what each worker thread is doing.

The replication channels created by the Group Replication plugin are named:

  • group_replication_recovery - This channel is used for the replication changes that are related to the distributed recovery phase.

  • group_replication_applier - This channel is used for the incoming changes from the group. This is the channel used to apply transactions coming directly from the group.

The following sections describe how to interpret the information available.