IPOUPDAT updates in place; EDIT does not. FDR compaction consolidates extents; it does not degas PDSs.
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List [[email protected]] on behalf of Paul Gorlinsky [[email protected]] Sent: Wednesday, December 21, 2022 10:28 AM To: [email protected] Subject: Re: PDS compression needs a new name - defoam? unfoam? degas? I hope someone has a better idea! I think they are talking about two different things here. 1) recapturing the de-occupied space in the data portion of a PDS 2) consolidating the multiple extents of a PDS 1) Unless things have changed a lot, PDS inserts and replacements, and even those of the same size, always get put at the end. Although, I believe IBM's PDS update program shipped with software distributions had code to update in place; I am not sure that TSO edit has that functionality. Why else did they come up with PDSEs ( and use VSAM )? Which I think might have performance issues. 2) Using FDRs defrag pulls the various extents together; defragging the dataset. ---------------------------------------------------------------------- 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
