Author Archives: Martin Packer

(Originally posted 2015-04-11.) It’s more like someone rich lighting their cigar with a hundred dollar bill. 🙂 Seriously, this post is about Coupling Facility Lock Structure False Contention and why it matters. It is, of course, inspired by a recent customer situation. Before I explain what False Contention is, and then go on to talkContinue reading “False Contention Isn’t A Matter Of Life And Death”

(Originally posted 2015-03-31.) As you know, we turn data into reports and try to make sense of it. One thing we’ve not done before is use colour in our textual and tabular reports. So here’s what I’ve learnt about how to make B2H use colour. Our Reporting Process But first a word or two aboutContinue reading “And Now In Colour”

(Originally posted 2015-03-22.) OA37826 really is the gift that keeps on giving: I got really nosy about Coupling Facility links when it came out [1] , though most customers didn’t get the added benefits of CFLEVEL 18 for a while. This post is about a customer installation which pointed out another benefit of the instrumentation.Continue reading “What’s The Latency, Kenneth?”

(Originally posted 2015-02-21.) … or probably more. I was going to use “Send In The Clones” but I’ve already used it – and someone who shall remain nameless once misremembered it as “Let There Be Clones”. Let there be clones, indeed. 🙂 So, how do I detect cloned CICS regions, for example? (And if youContinue reading “As Alike As Two Peas In A Pod”

(Originally posted 2015-02-15.) In He Picks On CICS I mentioned XCF traffic and CICS. This post is about a customer situation where looking at this traffic was important. Often I’m looking for topology (maybe “tourist information” to some of you). This time I have another motivation: Performance. In this customer saving z/OS CPU is important.Continue reading “CICS XCF Traffic Analysis – A Suitable Case For Treatment”

(Originally posted 2015-02-08.) I have a new conference presentation in mind. Its working title is “DB2 Through My Eyes”. Here’s the structure I’ve devised for it: Abstract What Is DB2? CPU General Purpose zIIP Memory Real Virtual I/O Database Subsystem Application Connections Performance Parallel Sysplex Coupling Facility XCF Specialist Subjects Restarts Workload Manager Stored ProceduresContinue reading “Proposed “DB2 Through My Eyes” Presentation”

(Originally posted 2015-01-10.) As I’m working with a couple of colleagues on a performance study I thought I’d list some “starter set” questions I’d ask about any customer’s WLM policy.[1] Before you go too far with this post you might like to read Analysing A WLM Policy – Part 1 and Analysing A WLM PolicyContinue reading “Some WLM Questions”

(Originally posted 2014-12-31.) It’s a little surprising to me that nobody complained about one aspect of the behaviour in the code in GreaseMonkey Script To Sum Selected Numbers In A Web Page. I’ve been muttering under my breath and I wrote the code. 🙂 This code naively assumes that in every web page there isContinue reading “I’m Surprised Nobody’s Complained :-)”

(Originally posted 2014-12-13.) This post is meant to inspire people who like programming the web to do simple tasks. It contains a sample Firefox GreaseMonkey [1] script, which I hope you will find useful. [2] Suppose you are looking at a web page, perhaps one with a table in, and you want to add upContinue reading “GreaseMonkey Script To Sum Selected Numbers In A Web Page”

(Originally posted 2014-12-07.) I thought I’d write about how I begin looking at virtual storage, occasioned by a customer who had a 24-bit virtual storage (878–10) ABEND[1] . Most of this is in our code, so easy for me to do. I hope you’ll find it similarly easy. You’ve had hints of this in HowContinue reading “How I Look At Virtual Storage”