Author Archives: Martin Packer

(Originally posted 2007-11-20.) I’m very pleased to note Peggy also has a developerWorks blog. She’s one of the leading lights in DB2 Development. Her blog is here

(Originally posted 2007-11-18.) Another trip down memory lane – prompted by the thread on IBM-MAIN of Batch LSR vs Hiperbatch. Batch LSR started out as a prototype by Paul Dorn of the IBM Washington Systems Center. He was contributing to a book on writing a subsystem but also trying to solve a problem with BatchContinue reading “Memories of Batch LSR”

(Originally posted 2007-11-15.) To whoever it is in Denmark that’s repeatedly hitting my blog today with a search for “dyndisp” and “ddf” I’d love to know what it is that is causing you to search for those two terms together. As you’re on my (day job) patch perhaps I should be talking to you directly.Continue reading “DYNDISP and DDF?”

(Originally posted 2007-11-12.) I’ve just re-read the XCF (74-2) and CF (74-4) sections of the z/OS Release 9 SMF Manual. There are some nice things in there… XCF (74-2) Number of buffer 1KB blocks by path (R742PUSE). This should tell you whether memory waste by over-specifying CLASSLEN is a problem. And some of the otherContinue reading “z/OS R.9 RMF Parallel Sysplex New Fields”

(Originally posted 2007-11-11.) It’s nice to see a flurry of activity in IBM-MAIN about Hiperbatch. And it’s more for the emotional reason of reminiscence than for any stunning insights that I’m blogging about it… Back in 1988 I ran a technical project in my then customer, Lloyds Bank, to evaluate Data In Memory (DIM). ItContinue reading “Memories of Hiperbatch”

(Originally posted 2007-11-09.) I was contacted by the team updating the SG24-7083 “DB2 Stored Procedures: Through The Call And Beyond” this past week. Their question was quite straightforward: “One of the statements in the book, in the chapter on WLM address space management states: To help analyze the use of resources by different types ofContinue reading “WLM-Managed DB2 Stored Procedure Address Spaces”

(Originally posted 2007-11-05.) Last week I attended GSE Conference for the first time in a long while. And I’m very glad I did. Let’s get the egotistical bit out of the way first… I very much enjoyed presenting Memory Matters in 2008. If you’ve seen me present it before you might notice some minor tweakings.Continue reading “GSE Conference 2007”

(Originally posted 2007-10-27.) I’m going to have to stop adding “(sic)” after every use of the word “Referer”. As in “Referer URL”. The term itself comes from one of the standard HTTP headers. And therefore is somewhat fixed. Despite giving my “wetware spell checker” a pink fit on a frequent basis. 🙂 Anyhow, in thisContinue reading “Hackday4 and Referer URLs”

(Originally posted 2007-10-17.) Following on from Coupling Facility Async / Sync Thresholds – They Are A’Changin’ I’ve been informed by Development there is a new improved write up on how the Dynamic Sync/Async conversion works in Chapter 6 of the z/OS Release 9: Setting Up A Sysplex manual. I’ve read it and it is VERYContinue reading “More on Coupling Facility Async / Sync Thresholds”

(Originally posted 2007-10-13.) APAR OA21635 is one of a rare breed: A change to the thresholds for z/OS’s automatic CF Request conversion. (I’m told this has only happened once before.) If you recall z/OS Release 2 (in 2001) introduced a very nice function that automatically converts Coupling Facility requests from Sync to Async, based onContinue reading “Coupling Facility Async / Sync Thresholds – They Are A’Changin’”