I could be wrong about VSAM compression here then. Maybe that is all CP compressed and I misunderstood by what mechanism that is done. We could not survive here without VSAM compression. Many of our VSAM files are > 4G space even compressed.
I do know we ARE using zEDC based on various internal communications I have seen. I just do not know the exact details. Peter From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Jousma, David Sent: Tuesday, April 16, 2024 1:13 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Anyone exploiting ZEDC? Peter, Interesting. IBM says VSAM does NOT exploit ZEDC. VSAM can be compressed, but it must all be done on CP, which would be expensive. Within a VSAM LINEAR dataset used as ZFS, ZFS will engage ZEDC. Dave Jousma Vice President | Director, Technology Engineering From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU>> on behalf of Farley, Peter <0000031df298a9da-dmarc-requ...@listserv.ua.edu<mailto:0000031df298a9da-dmarc-requ...@listserv.ua.edu>> Date: Tuesday, April 16, 2024 at 1:10 PM To: IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU> <IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU>> Subject: Re: Anyone exploiting ZEDC? I do not know what criteria the sysprogs here set things up. But we are successfully using zEDC here especially for our huge VSAM and GDG production files. I wish I could tell you more, but the sysprogs here are outsourced and getting answers from them requires official paperwork and bureaucracy that I have no business reason to cover. From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU>> On Behalf Of Jousma, David Sent: Tuesday, April 16, 2024 12:39 PM To: IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU> Subject: Re: Anyone exploiting ZEDC? Thank-you for this feedback. I’m starting to feel like this is a half-baked solution looking for a problem. I know of no way to systematically code for open for update…. Dave Jousma Vice President | Director, Technology Engineering From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU>> on behalf of rpinion865 <0000042a019916dd-dmarc-requ...@listserv.ua.edu<mailto:0000042a019916dd-dmarc-requ...@listserv.ua.edu>> Date: Tuesday, April 16, 2024 at 12:29 PM To: IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU> <IBM-MAIN@LISTSERV.UA.EDU<mailto:IBM-MAIN@LISTSERV.UA.EDU>> Subject: Re: Anyone exploiting ZEDC? At a prior life, we got the zEDC cards on a z15, and turned that on for PS datasets. But like you, we quickly learned that PS datasets opened for in/out processing (update in place) did not work. As a compromise, we narrowed down to new PS At a prior life, we got the zEDC cards on a z15, and turned that on for PS datasets. But like you, we quickly learned that PS datasets opened for in/out processing (update in place) did not work. As a compromise, we narrowed down to new PS GDG datasets. Also we looked at new PS GDG datasets over a certain size. We picked an arbitrary number of tracks/cylinders to apply the zEDC compression to. Once we did that, our production job abends disappeared and we started seeing a reduction in space usage on the storage groups where these datasets were being allocated on. Sent with Proton Mail secure email. On Tuesday, April 16th, 2024 at 12:16 PM, Jousma, David <000001a0403c5dc1-dmarc-requ...@listserv.ua.edu<mailto:000001a0403c5dc1-dmarc-requ...@listserv.ua.edu>> wrote: > Is anyone exploiting ZEDC data compression accelerator in your environments? > We recently licensed the enablement and are working through the issues in our > DEV environment. > > We initially enabled Extended Format/COMPACT ZP, for all DSORG PS datasets, > but are quickly finding that DFSORT, SAS, ISPF recovery datasets all have > issues. We’ve turned back off for now. > > There is no central location in any IBM doc(including recent REDBOOKS) that > discusses where we can and cannot leverage ZEDC. As it stands now, we had to > back out, and looking at taking a new approach in our ACS routines checking > for DSORG=PS, and then if not temp-dataset, or tape assign a DC with the > right options. > > What I am wondering is if anyone is further along that can share how they > rolled out? I really don’t want to have to make the applications teams have > to “opt-in” by coding a DC in their JCL or other dataset allocations. > > Dave Jousma > Vice President | Director, Technology Engineering -- 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 lists...@listserv.ua.edu with the message: INFO IBM-MAIN
