Author Archives: Martin Packer

(Originally posted 2010-01-16.) … swear at it. 🙂 No, I KNOW that’s not right – but it’s (for me) an irresistibly bad pun. And it’s a natural reaction, too. 🙂 In a recent customer situation I looked at the RMF Workload Activity Report data for a number of service classes. One WLM Sample count wasContinue reading “If The Cap Doesn’t Fit…”

(Originally posted 2010-01-04.) First of all, a happy and prosperous 2010 to one and all. As with most vacations it’s been a time partially filled with playing with technology and learning stuff there isn’t (legitimate) time to learn about during the rest of the year. So, lest the rest of this post make you thinkContinue reading “What I Did On My Vacation”

(Originally posted 2009-12-07.) If you use RMF Postprocessor you won’t see this one. If you use Service Units rather than CPU seconds fields in the SMF 72-3 record you also won’t see it. It’s only if (like me) you use the CPU time for zAAPs in your CPU Utilisation calculation that you’ll run into thisContinue reading “zAAP CPU Time Bug in Type 72 Record – OA29974 Is The Cure”

(Originally posted 2009-11-30.) Thanks to Marna Walle for pointing out this change: In z/OS Release 11 there is a requirement for an additional 1608 bytes of ESQA per address space. To put that in context, I’ll do some obvious maths: That’s about 1.6MB per 1000 address spaces. It just might be of interest to certainContinue reading “Plan Your ESQA Carefully For z/OS Release 11”

(Originally posted 2009-11-27.) A new set of function was recently made available for DFSORT via PTFs UK51706 and UK51707. In this post I want to talk about the new JOINKEYS function, and try to add a little value by discussing some performance considerations. I’ve had the code for a couple of months and have playedContinue reading “DFSORT Does JOIN”

(Originally posted 2009-11-22.) Our channel reporting has consisted forever of a single chart. Before I tell you what the chart looked like I’ll hazard that your channel reporting was about as bad. 🙂 See, it’s not something people tend to put much effort into. Our one-chart report basically listed the top channels, from the perspectiveContinue reading “Channel Performance Reporting”

(Originally posted 2009-11-09.) There’s a pattern I’ve seen over a number of test Parallel Sysplex environments over the past few years, a couple of them in situations this year: It’s not much use drawing performance inferences from test environments if they’re not set up properly for performance tests. Sounds obvious, doesn’t it? There are twoContinue reading “A Few Thoughts On Parallel Sysplex Test Environments”

(Originally posted 2009-11-08.) I’ve just submitted a set of slides to Slideshare. They’re not mine, they’re not new, they’re not even in a modern format. But they are a very good presentation worth preserving… In 1993 Curt Cotner presented a set of slides on the new DDF Inactive Thread support in Version 3 of DB2.Continue reading “DDF Performance – Version 3 – but still highly relevant”

(Originally posted 2009-11-08.) Apologies for being away. For a while I couldn’t get the blog to operate – as an author. And then I gave up trying. 😦 Count this as a "testing 1-2-3" post but also as notice I intend to back with more (hopefully useful) content soon. MUCH has happened in the "intermission".Continue reading “Hello World Again!”

(Originally posted 2009-05-07.) I’m reporting what I’m learning (or I think is significant) in conference sessions on Twitter. My Id is “MartinPacker” and I’m using the Hashtag “#zOS09” to tag my posts. Feel free to follow along. In principle you don’t even need to sign up to Twitter to do this. It seems more immediateContinue reading “European System z Tech Conference – Brussels 4-8 May 2009”