High CPU usage is found for the CA Workload Automation Agent for z/OS.
1. Large number of queued messages in the COMMQ file. In this case, there were 23,527 queued messages, and this caused high CPU usage as the zOS Agent tried to resend these messages every 2 minutes.
To determine the number of queued messages and the COMMQ file usage, execute the following zOS Agent modify command:
/F zosagm,ESPCOM DEST(-)
2. User retrieved the spool output from CA dSeries, and the zOS job SYSOUT is large (millions of records).
1. Large number of queued messages in the COMMQ file: If there's no z/OS job running (i.e., no tracking needed), execute the following zOS Agent modify command to delete all the queued messages: /F zosagm,ESPCOM FLUSH DEST(-)
2. Large job output: Use the zOS Agent initialization statement MSGLIMIT to limit the number of SYSOUT statements retrieved.
Example: MSGLIMIT 5000
Explanation: When the user retrieves the spool output from CA dSeries, only the first 5000 statement will be retrieved. In addition, the user gets a message box containing "event ... terminated due to msg limit exceeded".
Init statement "MSGLIMIT" is documented in the CA Workload Automation Agent for z/OS Installation and Configuration Guide.
Changing or setting the MSGLIMIT initialization statement requires a restart of the WA Agent for z/OS started task. As workaround, MVS modify command can be issued to set dynamically, like:
/F zos_agent_stc,MSGLIMIT 5000