JES job number is unique (guaranteed). Absent son other priority mechanism, jobs are selected FIFO with job class.
Jobs are queued at the end of conversion. This is unique to (at least) 1 /100th sec. If there are multiple converters, each is dispatched uniquely and my finish a few 1/00ths of a sec. apart. This has been the same since the days of HASP/OSMVT. Using the example below (unique jobname) there are 3 ways to guarantee execution order. 1) single initiator for that job class 2) use WLM managed inits 3) have job #1 submit job#2 .... The reason is that in a JES2 MAS, a job may be submitted on MVSA,, converted on MVSB, interpreted on MVSC and executed on MVSD. HTH, -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Farley, Peter x23353 Sent: Tuesday, April 14, 2020 3:00 PM To: [email protected] Subject: Order of execution for nearly-identical batch jobs with the same name [CAUTION: This Email is from outside the Organization. Do not click links or open attachments unless you trust the sender.] I have been confused by this behavior in z/OS for a long time now. Can anyone explain to me how JES2 selects which job will be executed next from a set of identically-named jobs at the same priority level in the same job class? Recently observed behavior has been all over the map. E.G., today I submitted four jobs from TSO all with the same job name. Each was assigned a sequential job number, like this: TSOUSERM 1001 TSOUSERM 1002 TSOUSERM 1003 TSOUSERM 1004 Observed execution order was: TSOUSERM 1004 TSOUSERM 1002 TSOUSERM 1003 TSOUSERM 1001 On a different day I saw that the order executed was third, second, fourth, first. These jobs execute the same number of PROC's and programs in the same order just using a different initial input file name. They are identical in every way except for the input file name. Why are these jobs not executed in the order submitted? That I guess is what I really don't understand. Fortunately I don't *need* them to execute in a particular order, I just don't understand why they do NOT execute in submission order. TIA for curing my ignorance. Peter -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ::DISCLAIMER:: ________________________________ The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. E-mail transmission is not guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or may contain viruses in transmission. The e mail and its contents (with or without referred errors) shall therefore not attach any liability on the originator or HCL or its affiliates. Views or opinions, if any, presented in this email are solely those of the author and may not necessarily reflect the views or opinions of HCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of authorized representative of HCL is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. Before opening any email and/or attachments, please check them for viruses and other defects. ________________________________ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
