IBM Z and LinuxONE IBM Z

IBM Z

The enterprise platform for mission-critical applications brings next-level data privacy, security, and resiliency to your hybrid multicloud.

 View Only

  • 1.  JES2 related questions

    Posted yesterday
    1. 1 Is there a global and local  for JES2 similar to JES3 ?
    2. 2.Can we stop/start JES2 while other tasks are running ?

    a.      What will happen to the job numbers, does it keep track of the ones that are already running ?

    b.     What happens when JES2 runs out of job numbers ?



    ------------------------------
    Puru Srinivasan DataPower Support
    Systems Engineer
    ANZ Bank
    ------------------------------


  • 2.  RE: JES2 related questions

    Posted 10 hours ago

    In JES2 there is no equivalent to JES3 local/global. 

    You can stop JES2 while the system is running, using a $PJES2,ABEND command.It will not affect active address spaces, but you can't introduce any new JES2 work until you restart JES2. 

    But why would you? 

    If you restart JES2, it will continue using the numbers it was using before you brought it down. 

    As you approach the maximum number of jobs(JNUM parameter) you will get $HASP050 warning messages. When you hit 100%, JES2 will not introduce anymore more work.  



    ------------------------------
    Mike Shorkend
    IBM Z platform specialist
    Shorkend
    Shoham
    ------------------------------

    Original Message


  • 3.  RE: JES2 related questions

    Posted 4 hours ago

    1) No. JES3 had a single global controlling multiple locals. JES2 doesn't use that model. Instead, it uses a MAS (Multi-Access Spool) of peer "members" that share SPOOL and a checkpoint; control is distributed and serialized via the checkpoint lock (on DASD or a coupling facility). There's no separate "global."

    2) Yes. Operators routinely quiesce/drain and stop JES2, then restart it. Use $P JES2 to withdraw/stop it cleanly; initiators/printers/etc. stop taking new work and finish what they're doing, then go inactive. After you restart ($S JES2), processing resumes. Already-executing jobs either finish during the quiesce/drain or (if you force/terminate) you'll need normal recovery

    A) JES2 keeps track of job identifiers and queues via the checkpoint; warm/warmish restarts rebuild state so in-flight/queued work is known

    B) JES2 job numbers are internal identifiers; you can reset the base with $T NUM,BASE=nnnnn (range 1–999999). JES2 assigns the next available number and won't reuse a number that's still present on the queues; when numbers cycle, reuse is only after the old job is gone. Separately, you can raise the maximum jobs on the queue with $T JOBDEF,JOBNUM

    I hope this has helped.



    ------------------------------
    Matheus Porsch
    Systems Administration - Kyndryl
    Brazil
    ------------------------------

    Original Message


Related Content