Symptom
Explanation
Solution
Related content

Symptom

On a few occasions when supporting a client, Pega engineers tried to perform a TRUNCATE action on the database table pr_sys_locks. DefragSysLocksDaemon was running on Stream nodes. This blocked the Pega database and caused the Pega application to stop working.

Explanation

A DSS for the class syslocks was set to run the defragment operation on the pr_sys_locks table every hour of the day (every 60 minutes).

When the defragmentation operation is running, if any UPDATE or CREATE operation is performed during defragmentation, you can expect operations on the Pega database to be blocked.

Solution

Update the DSS for the class syslocks to specify the following values:

Related content

Product Documentation

PEGA0056 alert: Defragmentation of the table associated with class System-Locks exceeded the configured time threshold

Defragmenting tables

System tables

Managing table turnover rates

Developer Knowledge Share

Pega Lock mechanism