Today is Hotsos Symposium 2008 Training Day — one full day with Tom Kyte. I haven’t registered for it so I took the chance to sleep until 10 this morning which was excellent idea considering that last night we were quite late going to bed thanks in parts to the joined demo that James Morle and Mike Erwin organized at the last presentation yesterday. I was in the James’ session and he was demonstrating how to hide latency problem with batching. I suspect that Mike, in the next hall, was showing the impact of MTU settings on cluster interconnect. The end result is that beer bottles traveled between the presentation halls and James ended up with about 3 packs of Guinness and Shiner Bock. That what kept us up longer last night.
James’ presentation itself was excellent — he explained that all performance problems can be caused by either skew or latency. You can’t normally fix skew issue so you just need to be aware and account for it. Latency can sometimes be shortened but usually insignificantly or it’s impractical (i. e. very expensive). It’s also very important to distinguish bandwidth and latency. I like his idea that the efficient way to solve latency is hiding it and there are generally two ways to do that — batching and threading. Improving bandwidth often doesn’t cause any performance improvement without taking latency into account. Very insightful talk. Thanks James.
It’s a pity that I couldn’t attend Mike’s session especially that he was looking for my help with his demo as I’ve been told. Sorry Mike! I’m also disappointed that I missed technical presentation that I was interested in. Well, I suppose I can catch up using the online material. Another unfortunate miss was Christian Antognini with new features of 11g query optimizer. Well, his book should be out in few months and it contains all this material.
While Chris was presenting in another hall, I enjoyed Kyle Hailey talk on Average Active Session metric that’s designed to give DBA a general idea of database load. Excellent review of history of Oracle Enterprise Manager performance development (Kyle is actually the one who designed the whole Performance tab in 10g Grid Control). The highlight was announcement of SASH – Simulated ASH or, as I call it, poor man’s ASH. It’s based on custom sampling of V$SESSION and presenting it in ASH format. It works on any edition and, the best part, it’s free! He also demonstrated ASHMON — basically, OEM Performance Tab light — written in TCL. Thanks for excellent tools Kyle — you rock!
Now I want to make you even more jealous and mention couple details of the evening. The first destination was shopping in Galleria Dallas. Some shopping and beers next to skating rink. Then we moved at the Ginger Man pub — they served so many different beers (probably, about a hundred) that I had difficulty to make my choice. Then we saw what was the beer of the week — Live Oak Big Bark Pale Amber beer. Since there were four OakTable Network members, it was the natural choice. It turned out to be great beer and I will definitely save this name in my head. After Ginger Man, we moved to Ghostbar in W Hotel — very trendy environment. Thanks to Stefan Knecht for putting us to the VIP guest list — we wouldn’t get there otherwise.
Now bad news… My family is arriving in couple hours and this fact is great news. The problem is that we are expecting snow again tonight and I’m afraid that Olga’s deja-vu can have brutal impact tonight. Anyway, I’m out of here — car rental pick up is arriving any minute now and I need to find my suitcase.