Tuning Letter 2019 No. 1 Available

by | May 15, 2019 | Cheryl's List

Hi All,

The latest 113-page issue of Cheryl Watson’s Tuning Letter is now available on our publications website.  If you are not a Tuning Letter subscriber, you can view the Table of Contents here.

This issue opens with Cheryl’s Trip Report from SHARE in Phoenix. This was the first SHARE in 40 years that Cheryl attended but didn’t present at.  But don’t think for a minute that she put in any less effort.  Being Cheryl, she picked out and attended the sessions that she thought would be of the most interest to our readers, or the ones where she could best provide input to influence vendor’s future directions.  Have a read of Cheryl’s Trip Report to find out how she was helping you at SHARE in Phoenix.

How many times have you experienced a serious outage, only to discover that there was a warning message on the console, informing you of the impending doom?  Of course, you only discover the message after the outage.  Or even worse, when you discover the message, a colleague says “Oh, I saw that message, but I didn’t think it was important.” Grrr.  We’ve all been there.  But to try to reduce the number of these occasions in the future, our colleague Mario Bezzi wrote an IMPORTANT_MESSAGES health check that runs under the IBM Heath Checker for z/OS infrastructure. The program checks console messages as they are issued against a pre-defined list of messages.  The package includes a list of messages that have been identified as being really important by the product owner, or in a Redbook, or an IBM presentation, or an IBM Techdoc.   You can also add your own messages.  If any of the messages in the list are issued, Mario’s health check will generate a Health Checker exception.  This gives you a single place (the SDSF CK option, for example) to check whenever your system starts misbehaving.  The package containing the code and documentation will be available soon on the Free Tools page of our website.

z/OS 2.3 is the last z/OS release that will support user key common storage.  IBM issued a Statement of Direction to that effect in 2017, and since z/OS 1.9, the default setting of the VSM ALLOWUSERKEYCSA parameter has been NO.  However, there are two related functions that are also going away in z/OS 2.4, and they have received very little attention until recently.  In fact, as of today (May 15th), the Parmlib parameters that control those functions still have not been documented in the z/OS MVS Initialization and Tuning Reference.  IF you are using one of those functions, addressing that might be a non-trivial task, so we strongly encourage you to read the Bye Bye User Key Common Storage article now, and not the week before you start installing z/OS 2.4.

Speaking of z/OS 2.4.  As you know, IBM previewed the next z/OS release on February 26th, in IBM US announcement letter 219-013.   Our z/OS 2.4 Preview article picks out the enhancements that we think are especially interesting to our readers, and also points out some important dates.  Even if you don’t plan on moving to z/OS 2.4 right away, it is worthwhile to check our review so that you know what lies in your future (or in the case of functions that are being discontinued, what does not lie in your future!).

Finally, it is nearly two years since we launched our subscriber-only publications site.  The site contains every Tuning Letter, right back to Cheryl’s first one in 1991.  It also contains hundreds of presentations and other material delivered by Cheryl over the years.  And it is all accessible via a powerful search engine.  We have received many kind and insightful comments from our readers over the last two years.  We have also recently made some enhancements to the site, so we thought that this would be a good opportunity to provide our subscribers with updated information and tips about how to get the best value from the website.  If your company has a subscription to the Tuning Letter, but you have not registered for a userid on the site, we strongly encourage you to do so.

Plus, of course, the Tuning Letter has all the usual information about interesting or important APARs, new IBM Redbooks and Techdocs, and upcoming conferences.  We hope that you will have time to read it and send us your feedback.  The more comments we receive, the better job we can do of addressing your needs.  Bye for now, and as Cheryl would say, ‘Stay Tuned’.

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