𝗪𝗵𝘆 𝗔𝗿𝗲 𝗦𝗼𝗺𝗲 𝗝𝗼𝗯𝘀 𝗣𝘂𝗿𝗴𝗲𝗱 𝗳𝗿𝗼𝗺 𝗝𝗛𝗦 𝗘𝗮𝗿𝗹𝗶𝗲𝗿 𝗧𝗵𝗮𝗻 𝗢𝘁𝗵𝗲𝗿𝘀?

In JHS (Job History System), we noticed that some jobs are purged from JHS sooner than other jobs.

We dug through the installation libraries below and found that JHS groups jobs by a Job Group number, ranging from 0 to 15.

HLQ.JHS.PARMLIB(EXITS)

HLQ.JHS.JHSASM(JHSGRPM1)

HLQ.JHS.PARMLIB(JHSPARMS)

JHS uses the Job Group number to determine the job retention period. These groups can be used to categorize jobs based on their retention requirements, such as daily, weekly, monthly, or annual jobs. Up to 16 Job Groups (0–15) can be specified.

 
The name of the JHS exit that assigns the Job Group number to jobs can be found in HLQ.JHS.PARMLIB(EXITS).
 
HLQ.JHS.PARMLIB(EXITS)
 
<EXIT>
  <TYPE>JOBGROUP</TYPE>
  <MODULE>JHSGRPM1</MODULE>
</EXIT>
 
The sample code for the JHS exit JHSGRPM1 can be found in:

HLQ.JHS.JHSASM(JHSGRPM1)
 
IF NAME=-------D
  GROUP 0
ENDIF
IF NAME=-------W
  GROUP 0
ENDIF
IF NAME=BXXXXXXD
  GROUP 4
ENDIF
IF NAME=MXXXXXXW
  GROUP 14
ENDIF
 
In PARMLIB(JHSPARMS), each Job Group is associated with a retention period specified in number of days.
 
HLQ.JHS.PARMLIB(JHSPARMS)
* NUMBER OF DAYS RETENTION OF JOB SUMMARY DATA
RETAIN              010    JOB GROUP 0
RETAIN1             005    JOB GROUP 1
RETAIN2             007    JOB GROUP 2
RETAIN3             012    JOB GROUP 3
RETAIN4             014    JOB GROUP 4
RETAIN5             018    JOB GROUP 5
RETAIN6             020    JOB GROUP 6
RETAIN7             022    JOB GROUP 7
RETAIN8             024    JOB GROUP 8
RETAIN9             030    JOB GROUP 9
RETAIN10            060    JOB GROUP 10
RETAIN11            091    JOB GROUP 11
RETAIN12            120    JOB GROUP 12
RETAIN13            150    JOB GROUP 13
RETAIN14            160    JOB GROUP 14
RETAIN15            170    JOB GROUP 15
 
Therefore, jobs assigned to different Job Groups can have different retention periods in JHS, which explains why some jobs are purged sooner than others.