What Should I Do If a Real-Time Job with PostgreSQL/GaussDB as the Source Fails to Be Started and Error "all replication slots are in use" Is Reported?

Symptom

A real-time job with PostgreSQL/GaussDB as the source fails to be started and error "all replication slots are in use" is reported.

Possible Causes

The maximum number of replication slots has been reached.

Solution

• Increase the maximum number of replication slots.
  On the PostgreSQL/GaussDB parameter management page, set max_replication_slots to a value greater than or equal to the number of real-time jobs with PostgreSQL/GaussDB as the source. The change takes effect only after the database is restarted.

  Figure 1 Setting the parameter
  
• Delete the replication slot that is no longer used.

  For details about how to delete replication slots, see How Do I Manually Delete Replication Slots from a PostgreSQL Data Source?.