Believe what you want, but the fact is that DISP=NEW for DASD physically creates a dataset. whether it also writes an EOF depends on how you're configured.
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List <[email protected]> on behalf of CM Poncelet <[email protected]> Sent: Thursday, August 8, 2019 6:52 PM To: [email protected] Subject: Re: CPU time cost of dynamic allocation FWIW I hesitate to believe that PASSED/DELETED implies that the temp datasets were ever physically created on DASD - unless they were OPENed for OUTPUT in-between. I think the *physical* alloc happens only on an OPEN DCB with MACRF=(PM/L). Have you tried something like the following with IEFBR14? '//WHATEVER DD DISP=(,CATLG), '// DSN=<whatever>, '// DCB=(RECFM=VBA,LRECL=137,BLKSIZE=27998,DSORG=PS), '// SPACE=(CYL,(9999,2000)),VOL=(,,,20) The VOL=(,,,20) would give you 320 extents. The SPACE=(CYL,9999) would hopefully be unable to allocate the primary 9999 CYLs on the first 16 extents, so would have to allocate the remaining CYLs on second/third/etc. DASD volumes. An ISPF "3.2" would show on which VOLSERs the dataset had been allocated. An ISPF "3.4" with "V" (if memory serves), and specifying the first VOLSER from the "3.2", would then show how much free space and how many extents were still available on it. If no free space or extents are left on it, do a "3.4" but now specifying the fully qualified DSN *and* the second VOLSER from "3.2". If some of the dataset has been physically allocated on this second DASD VOLSER, the "3.4" should display it; else, it has not been physically allocated on this DASD. Just my ha'penny. On 08/08/2019 20:17, Charles Mills wrote: > I see > > IEF285I SYS19218.T143507.RA000.xxx00114.R0105346 PASSED > IEF285I SYS19218.T143507.RA000.xxx00114.R0105347 PASSED > IEF285I SYS19218.T143507.RA000.xxx00114.R0105348 PASSED > ... > > And > > IEF285I SYS19218.T143507.RA000.xxx00114.R0105346 DELETED > IEF285I SYS19218.T143507.RA000.xxx00114.R0105347 DELETED > IEF285I SYS19218.T143507.RA000.xxx00114.R0105348 DELETED > ... > > So it looks to me like DSCBs were actually created. > > Charles > > > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On > Behalf Of CM Poncelet > Sent: Wednesday, August 7, 2019 12:34 PM > To: [email protected] > Subject: Re: CPU time cost of dynamic allocation > > >From years ago, I *think* an IEFBR14 step with DISP=(,CATLG) [or > (,PASS)] does not physically allocate a dataset on a VOLSER but only > registers it in the usercat. Have you checked whether it is in the VTOC? > > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
