Node and cluster default job schedulers

Pega Platform includes job scheduler instances that persist system state and that clean obsolete data for a node and for a cluster.

Node cleaner

By default, the node cleaner job scheduler (pyNodeCleaner) runs the Code-.pzNodeCleaner activity on all the nodes in the cluster. It cleans up expired locks and outdated module version reports.

Cluster and database cleaner

By default, the cluster and database job scheduler (pyClusterAndDBCleaner) runs the Code-.pzClusterAndDBCleaner activity on only one node in the cluster, once every 24 hours for housekeeping tasks. This job purges the following items:
  • Older records (instances) from log tables
  • Any requestors that have had no activity during at least 48 hours
  • Passivation data for expired requestors
  • Rows from the pc_events database table according to the EventsRetentionPeriod dynamic system setting (the default retention period is 90 days)
  • Any nodes that have not responded to the pulse for 30 days
  • Expired locks
  • Old usage data if usage tracking is enabled
  • Cluster state data that is older than 90 days

Once per day, this activity calls Log-Usage.UsageCleaner, which trims older rows of the pr_perf_stats table (corresponding to the Log-Usage class). This activity starts a stored procedure, passing a number of days to retain based on the value of the pxProcess.pxLogUsage RetentionPeriod property. The default is 30 days, which can be updated through an entry in the prconfig.xml file or in a dynamic system setting.

You can change the idle requestor purge criterion to a value that is less than 48 hours by overriding the setting initialization/persistrequestor/contentExpiryThreshold, which is in seconds.

You can optionally create an activity that is similar to Code-.pzClusterAndDBCleaner and associate it with another job scheduler to purge other outdated information and to recover tablespace. Ensure that the job scheduler has access to the needed ruleset versions and does not purge instances that are referenced in other tables.

Persist node and cluster state

Node state is saved by pyPersistNodeState on node start up. Cluster state is saved once a day by the pyPersistClusterState job scheduler. Cluster state data is saved for 90 days and is purged by the pzClusterAndDBCleaner job scheduler.