Graham Wood customer meeting

Last Thursday, my customer got the chance to have a customer account meeting with Graham Wood at Oracle Netherlands. Normally this would be a DBA affair, but luckily my customer thought it was a good idea to have two developers join the three DBA's. And I was one of the lucky two developers, since I get to solve quite a lot of performance problems, that are spotted by our DBA's.

As a developer I do not have a lot of experience with tools like AWR, ADDM and ASH, so I did some prior reading to know a little more about what the tools do, and I also read the powerpoint of Graham's presentation at last year's Miracle Database Forum, called You Probably Don't Need SQL*Trace. Now that's a title that draws my attention of course. At first glance, the screens from the EM Diagnostic Pack to view ASH data, look very similar to the ones I am familiar with from Indepth for Oracle, which we use.

In the one-and-a-half-hour conversation, Graham answered three of our prepared questions, mostly RAC-related. And since time allowed it, I was able to ask a question myself about the previously mentioned presentation. In Indepth for Oracle it is very easy to spot when and where performance problems occur, since our systems are pretty well instrumented. However, when you drill down to the SQL-level and asking for the plan, you get to see an explain plan instead of the row source operation. This is not useful and therefore the DBA's usually send the SQL statements to me or a colleague to have a closer look. It would be nice if the row sources were displayed together with the time spent on each row source. And this is exactly what ASH will contain. So you are able to drill down from instance to session to module to SQL to row source level. Now that sounds promising. Unfortunately I don't recall in what version it will be available. Maybe it is already available now. If you know, please leave a comment.

Also, Graham was surprised to find out that version 8 of Indepth for Oracle also contains "real execution plans" as can be read here.
According to Graham that is hardly possible, as the information is only available to Oracle. As we will likely upgrade Indepth for Oracle, we will soon find out if it is truly so.

Graham also drew a picture on the whiteboard showing approximately how the first screen of the new interface will look like. Instead of having equally sized pictograms for each instance, it will show all instances as rectangles. The more time they have consumed, the larger the rectangle will be. And all rectangles will be displayed on one screen with the larger ones appearing at the top left corner, and the small - probably developer instance - rectangles at the lower right corner. Instances that show far more worse performance than usual will be displayed red. This sounds like a great interface, especially when the DBA has to monitor LOTS of databases.

I very much enjoyed the session, and although I was feeling a bit overwhelmed by all the information packed in such a short amount of time, I am glad for having had this opportunity. Graham's tour will now lead him to three different cities in Germany and after that he is off to Turkey.