My HackDay 5 Project – z/OS System Logger Analysis

(Originally posted 2008-04-27.)

As some of you will know IBM has a twice-yearly “HackDay” programming fest. And the latest – HackDay5 – was last Friday. Couched as a competition it isn’t really… It’s a heck of a sight more cooperative than that. (Else I wouldn’t have got involved.) I’ve participated in all five we’ve had over the past two years. And it’s been great fun. This time – for the second time – I’ve physically gone to Hursley to take part in the local event.

New for HackDay5 was the “zHackDay” initiative – which I take “responsibility” 🙂 for…

The idea was that mainframe-related hacks were labelled as such. Partly to goad mainframe folks into participating, and partly to point out to non-mainframers that we’re just as capable of doing fun hacks as everyone else.

So, was my project exciting?

Probably not – but then I wasn’t personally aiming to set the world alight. I’m more interested in getting useful stuff done that I wouldn’t ordinarily get around to. So my project is basically to map the SMF 88 System Logger records.

This has been done before – and indeed there’s a z/OS-supplied utility to report on System Logger from Type 88 data.

So why would I “reinvent the wheel”?

The main reason is that it allows me to put the data together with other things. Such as SMF 74 Subtype 4 Coupling Facility data. If a logstream uses a coupling facility structure the SMF 88 record tells you the structure’s name. (This is similar to a recent trick where the 74-2 XCF data tells you the structure name and my code looks up the 74-4 view of the structure.)

Actually I know relatively little about System Logger – but I’m learning fast. And that’s the other reason I did this hack… To enable me to learn.

Finally, if I discover something’s missing from the data I can use real customer situations to discuss with Development what’s needed.

So, how far did I actually get? I got the Type 88 Subtype 1 (Logstream Activity) data mapped and summarised at the (e.g.) hourly level. And some very simple reporting. I haven’t (yet) done the same for the Type 88 Subtype 11 (Coupling Facility Structure) data. But that should be easy and straightforward.

So, if you’re sending me data I’m going to be asking you to send me your Type 88 data as well. I hope you’ll find what I do with it to be useful.