On Mon, 22 Apr 2013 22:33:59 -0500, Anthony Fletcher <[email protected]> wrote:
>We have a customer running on a z800 in a capped LPAR. >We just converted them from z/OS 1.12 to z/OS 1.13 and have found that >performance has degraded. > >They are looking at a list of data sets - approx 98,000 under a HLQ, say ABCD >with the Initial view set to 2. SPACE > >On z/OS 1.12 this list was retrieved in under 10 seconds >On z/OS 1.13 this list took 20 Minutes to return. > >If the Initial View is changed to 1. Volumes >then the performance is much the same. > >The view is paged right to get the space values, on the 1.12 system it comes >back in seconds > > on the 1.13 system it takes minutes to come back. > >Many of the 98,000 data sets are on TAPE or migrated. > >Anyone recognise a feature that came with z/OS 1.13 that might cause this >change in behaviour? > Hmmm. I don't think this is related to z/OS 1.13 per se. But obviously something seems wrong. The first thing I can think of is maybe the COFVLFxx member was not carried forward and catalogs are not using VLF or perhaps your client was using enhanced catalog sharing and that isn't active. But even so, from 10 seconds to 20 minutes seems extreme even without VLF or ECS. I say this because you mentioned that even the initial view of VOLUME takes a long time and that is just a catalog lookup and that has to be done before the space usage is looked at in the vtocs. What if you try doing some lists without a catalog? Use a HLQ and an generic volser like SYS* for example. Another thing you can try is to use the sample CSI (catalog search interface) exec SYS1.SAMPLIB(IGGCSIRX) or my modified sample from my web site (CATSRCH) and see how that performs. That could help narrow down the performance issue. Regards, Mark -- Mark Zelden - Zelden Consulting Services - z/OS, OS/390 and MVS mailto:[email protected] Mark's MVS Utilities: http://www.mzelden.com/mvsutil.html Systems Programming expert at http://expertanswercenter.techtarget.com/ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
