Author Archive: Gail

I skipped the keynote on Thursday to spend some time in the SQL Lounge. One of the people there did a demo of a set of scripts, jobs and reports called DMVStat. It’s up on the net somewhere. I don’t have the link right now, but I’ll see if I can dig it up in a day or so.

The first session was on analysing the plan cache. It wasn’t a particularly deep session, just covering how to get execution plans in SQL 2005 (the plan cache DMVs).

The SQL CAT team did a presentation on high availability in the afternoon. Not as good as the session on MySpace, but that would be hard to top.

Bob Ward ran the only level 500 session of the conference, covering debugging difficult problems. The kind of problems that he sees as a senior escalation engineer at PSS. He discusses latch waits, slow IOs, corrupt databases, access violations, memory problems and unexpected shutdowns. It felt something like standing under a waterfall, but it was a brilliant session.

The afternoon wrapped up with a discussion on practical performance monitoring by Andrew Kelly. He went over perfmon, profiler, wait stats, disk stats and showed some techniques for managing the load of data.

All in all, that was a very successful day. One more day to go… 

Wednesday at PASS is the first day of the real conference. The day started off with the usual keynote. Ted Kummert of Microsoft went through the data vision that microsoft has, complete with a whole lot of demos.

The part that most caught my eye was the demo of some new SQL 2008 features, including the resource governor with its ability to restrict resource usage depending on properties of the connection (eg application name, host name, login name, etc). The policy-based management should make policy enforcement much easier now, especially since policies can be applied across multiple servers in one operation.

The new spatial data types look cool. I can’t see immediate uses for them myself, but I do like them.

Finally, something that had the entire audience cheering, intellisense in management studio. About time. Something that I also saw but wasn’t mentioned was what appeared to be syntax checking as you type, much like visual studio has. Not sure how far that goes (to objects or just to key words) but it does look interesting.

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The second day pre-conference that I attended was by Kalen Delany, all about query plans.

The first part of the session was an overview of the various methods of getting a query plan, from the showplan options for estimated plans, to the profile options for actual execution plans, the graphical options and the usage of SQL Profiler to get both actual and estimated plans.

She then briefly covered sub-optimal plans, without going into detail on query tuning. Stuff like cardinality estimation errors and potentially slow operators (scans, sorts, hashes)

After lunch we delved into details on the plan cache, including what constitutes a plan, how to view them and what conditions there are around plan reuse. This covered adhoc plans, prepared plans and object plans (stored procedures), as well as recompiles and the downsides of plan reuse.

Finally there was a section on query hints and plan guides, for use when the optimiser just won’t do what you want it to do.

The evening was a great deal of fun, with the opening reception and the SQLServerCentral party. I had the opportunity to take part in the quiz bowl. Got eliminated in the first round (damn movie questions) but was still good fun. Won a couple books. More reading material is always a good thing.

Spent the first day of the conference at the PSS Bootcamp. The PSS guys always put on a good show as they take people through what they do to solve customer’s problems.

The first part of the day was devoted to a performance tuning methodology. What do you do when the users are complaining that the server’s slow. The presenter went through the methodology that the PSS engineers use when presented with a performance problem.

Most of the process is aimed at finding the problem query or identifying a resource bottleneck on the server.

If the problem is currently occurring, one of the main tools is the performance dashboard, a new report introduced into Management studio with SQL 2005 SP2

If the problem is not currently occurring, then it’s necessary to use SQLDiag, profiler, perfmon or a combination of them. A very interesting new tool that they introduced is a data aggregation and reporting tool for performance data – SQL Nexus. The updated version is supposed to be available by end November.

The session finished with a brief look at some of the new features of SQL 2008 that would help out with performance issues. One of the big ones, at least for me, is the performance warehouse. SQL can be configured to collect performance related data continuously in the background and save that into a data warehouse. There are a collection of reports built into management studio that report off this data. Used properly, that should make finding performance problems much easier than currently.

The other feature in 2008 that looks fantastic – a dependency checker that actually works. Sounds great 

Well I’m off to PASS tonight. total of 18 hours of flying and 7 or so hours sitting around in London Heathrow airport. What fun.

Looking forward to the conference. Hopefully I’ll get a chance to chat with some people I met last year.

I’ll probably be reporting on some of the sessions while I’m there. If there’s anyone who reads this blog that’s going to be at pass, look me up and say hi. Just look for someone wearing a nametag  with the name ‘Gail’ and country ‘South Africa’