Cheryl’s List #72 – October 8, 2002

by | Oct 8, 2002 | Cheryl's List

1. New z/OS Migration Guide
2. New WLM APAR
3. New WLM Tool
4. Steve Samson’s New Book
5. Update to TUNING Letter 2002, No. 5
6. We’re still in Japan

1.  New z/OS Migration Guide

On September 27, IBM announced the availability of the OS/390 2.10 to z/OS 1.4 Migration manual, officially called z/OS Migration Version 1 Release 4.  Greg Daynes, IBM Senior Technical Staff Member, notes: “The book documents all migration considerations for a customer coming from an OS/390 2.10 system going to a z/OS 1.4 system, including general actions, element specific actions, actions related to upgrading hardware, and even actions related to migrating to z/Architecture.   It consolidates information from 34 z/OS books, 5 IBM Redbooks, 5 WSC Flashes, numerous APARs (including Info APARs) and a handful of IBM and user SHARE presentations.”

This 300-page manual is an incredibly complete guide.  Because most installations are planning to make that exact move (OS/390 R10 to z/OS 1.4), this single guide will be used by the majority of your peers.  I’m very impressed with the book’s ease of use and clear explanations.  Especially helpful is the fact that stages are clearly delineated, and you can accomplish many of the tasks before even installing z/OS 1.4.  Don’t wait until the last minute – start now.  The link to the guide can be found on the home page of z/OS at http://www.ibm.com/servers/eserver/zseries/zos.  This book should make for some very smooth migrations!

2.  New WLM APAR

In previous newsletters and presentations, I’ve mentioned a problem where the initiators, running in SYSSTC (instead of the old PVLDP), could impact online response times.  Lawrence Jermyn from Fidelity Investments recently reported that an APAR had been opened to address the situation.  APAR OW55344 (New Function) was opened on 9/4/02.  Although most installations will not be affected by this problem, a few will find it indispensable.  You might want to track this one.

3.  New WLM Tool

Robert Vaupel of the IBM WLM team provides the following update:

“In order to assist customers in finding out whether they may run into a problem with their execution velocities when they migrate from OS/390 to z/OS we have now published a tool which allows them to project the change in execution velocities when they migrate from OS/390 to z/OS.  The tool assumes that APAR OW55665 will be applied to the z/OS system. This APAR hasn’t been closed yet but will be closed soon. Nevertheless we provide the tool already to allow customers to plan for the migration.  The tool is named WLMZOS and is available at:http://www-1.ibm.com/servers/eserver/zseries/zos/wlm/tools/.

“When you use the tool you will probably notice that there is still a recognizable decrease in execution velocity for service classes with very low utilizations while the difference for service classes with higher utilization diminishes. For the data I looked at so far it seems that this doesn’t require any action by the customer or only minor adjustments.”

Many thanks, Robert, for this handy new tool.  I discussed the problem with execution velocities in z/OS in the last three TUNING Letters (#3, #4, and #5), as well as Cheryl’s List #68.

4.  Steve Samson’s New Book

Steve Samson has produced the next edition of his very popular book, “MVS Performance Management“.  This is the “z/OS Version 1 Edition“.  Steve has made major changes and additions to this edition.  You can order the book for $50 at https://www.setsystems.com/cgi-bin/form?Product=1408.

5.  Update to TUNING Letter 2002, No. 5

Thanks to Frank Bernhardt of COMPAREX Information Systems in Germany for noticing a typo on page 40 of TUNING Letter 2002, No. 5.  The MSUs for a 2064-103 should be 112 instead of 119, and the MSUs for a 2064-1C3 should be 119 instead of 144.

On page 12, I wrote: “WLM, in z/OS 1.3, provides a new API called IWMERES, which allows a program to reset an enclave.  The SDSF team created an SPE (PQ50025) for z/OS 1.2 to use this new API.”  Jürgen Holtz of the IBM WLM team pointed out that some people therefore thought that this facility was available on z/OS 1.2.  I should have been more specific.  WLM, in z/OS 1.3, provides a new API called IWMERES, which allows a program to reset an original independent enclave.  The SDSF team created an SPE (PQ50025) for SDSF 1.2 that only becomes usable in z/OS 1.3 and later.  That is, you need both z/OS 1.3 and the SPE.

6.  We’re still in Japan

We’re having a wonderful time with our two-month stay in Japan.  There’s not much time for email, so I apologize to anyone to whom I’ve not replied.  We’re expecting to return in mid-November.

Stay tuned!

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