I think someone mentioned WAD. If I remember correctly when using the +1 the system does an enqueue on the BASE as part of the process. The enqueue is not release until the file is closed. I believe this is done to insure proper "roll in" of the new generation.
I believe this same behavior happens when you are reading a GDG by the +1 or +0 or whatever. Any new allocation of the GDG will fail or hang until the other job closes the file it is reading. For reads I have gotten around this by doing the allocation using the full dataset name. Thanks.. Paul Feller AGT Mainframe Technical Support -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Paul Gilmartin Sent: Tuesday, September 12, 2017 15:08 To: [email protected] Subject: Re: GDG +1 dynamic allocation collision between two concurrent jobs On Tue, 12 Sep 2017 22:42:47 +0300, Binyamin Dissen wrote: > >What if job #1 now allocates +2? > What does a relative generation number greater than +1 mean? Must be something because the JCL Ref. says: v The numeric portion (not + or -) of a relative generation number must be expressed in 1 to 3 numeric characters. For example, +100, -002, +4, -09, 000. Does allocating MANAGED.TEST.GDG(+100) leave a gap of 99 values in the numbering? Or does it fill in the 99 not mentioned generations with new data sets? >+1 remains that thru the job. > >On Tue, 12 Sep 2017 11:54:04 -0500 Kirk Wolf wrote: >:> >:>BPXWDYN RC= 34603008 (0x2100000) >:>IKJ56225I DATA SET MANAGED.TEST.GDG ALREADY IN USE, TRY LATER+ >:>IKJ56225I DATA SET IS ALLOCATED TO ANOTHER JOB OR USER >:>IEFA110I DATA SET CONTENTION >:> I agree with Kirk's surmise that the ENQ conflict is on the base, not on the generation, so +2 is probably not a circumvention. What does a Display GRS from the console or from DDLIST show? -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
