Static probes are being gradually integrated into MySQL. As of MySQL 6.0.9, there are around 55 static probes. To use the static probes, you will have to supply an extra option to the configure script, --enable-dtrace. After the build is over, start mysqld. Now open a terminal, and type $pfexec dtrace -l | grep mysql. You should see something like this:

135 mysql23509            mysqld __1cQdispatch_command6FnTenum_server_command_pnDTHD_pcI_b_ command-done
  136 mysql23509            mysqld __1cQdispatch_command6FnTenum_server_command_pnDTHD_pcI_b_ command-start
  137 mysql23509            mysqld __1cQclose_connection6FpnDTHD_Ib_v_ connection-done
  138 mysql23509            mysqld             handle_one_connection connection-start
  139 mysql23509            mysqld __1cMmysql_delete6FpnDTHD_pnKTABLE_LIST_pnEItem_pnLst_sql_list_LXb_b_ delete-done
  140 mysql23509            mysqld __1cHhandlerNha_delete_row6MpkC_i_ …

Just came across this paper:  Optimizing MySQL Database Application Performance with Solaris Dynamic Tracing

Looks useful.

Just came across this paper:  Optimizing MySQL Database Application Performance with Solaris Dynamic Tracing

Looks useful.

This Thursday (February 12th, 14:00 UTC), MC Brown will give a MySQL University session on Using DTrace with MySQL. MC has been involved not just with documenting DTrace but also with DTrace development; see his recent blog post for details.

For MySQL University sessions, point your browser to this page. You need a browser with a working Flash plugin. You may register for a Dimdim account, but you don't have to. (Dimdim is the conferencing system we're using for MySQL University sessions. It provides integrated voice streaming, chat, whiteboard, …

My presentation at LOSUG on tuesday went down like a house on fire - I think it would be safe to say that the phrase for the evening was ‘It’s a cache!’.

For that to make sense, you need to look at the slides, which are now available here.

Attendance was great, but it seems the last minute change of day meant that some people missed the session. We had 151 people register, and about 80 turned up on the night.

Next Tuesday (27th Jan), I’ll be speaking at the London OpenSolaris User Group again. For those that follow the LOSUG meetings, we normally the third thursday of the month, but due to the overwhelming popularity of the event this month (more 100 registrations so far) we have had to push the event back to the last Tuesday of the month.

This month, I’ll be talking about the DTrace probes that we have added into MySQL and demonstrating their use and functionality. Along the way I’ll also cover some of the internals of MySQL and how it works (and how they relate to the DTrace probes we’ve added), how to use the probes to analyze and diagnose your queries, and how I’ve already used the DTrace probes to provide information up to the Query Analysis functionality within …

This Thursday (December 18th), Martin "MC" Brown will talk about using DTrace with MySQL. MC is the Solaris (and, naturally, DTrace and ZFS) expert on the Sun Database Group documentation team. He's helped the openSolaris team port MySQL to openSolaris.

Note that we'll be using a new session address / Dimdim URL:

http://webmeeting.dimdim.com/portal/JoinForm.action?confKey=mysqluniversity

You can bookmark this address, since it will remain valid for all future MySQL University sessions. Remember, though, that the meeting room will open only 15 minutes before the session starts.

Dimdim is the conferencing system we're using for MySQL …

There have been plenty of blog entries and writings about the MySQL Query Analyzer, for what I think are good reasons. Labeling it a potential Killer App, causing many MySQL users to become paying Sun customers, may be a daring thing. However, the Query Analyzer might very well have what it takes. The key benefit of it is that it identifies the source of performance bottlenecks. In that sense, one could perhaps instead call it a profiler, as it analyses the set of all queries going on, as opposed to an individual one. One person to whom I described it said “ah, so …

So it’s been a while since I’ve hit my blog, but I feel compelled to respond to Baron’s post, and many of the other (perhaps short sighted) criticisms out there against this new functionality that we’ve been working on for so long.

Everybody seems to be saying that this functionality should be implemented in the server, or that the better way to do this is to use these patches which add functionality to the logging that MySQL already provides. Well guess what people - what does that give you, other than some more details on you queries?

More I/O.

What’s bad on a database server?

More I/O.

Query Analyzer, whilst it does currently use a proxy to collect the statistics, doesn’t hit your disk at all. Everything is collected and aggregated in memory, it …

Currently I'm working hard to find and remove scalability
bottlenecks in the MySQL Server. MySQL was acquired by Sun
10 months ago by now. Many people have in blogs wondered what
the impact has been from this acquisition. My personal
experience is that I now have a chance to work with Sun
experts in DBMS performance. As usual it takes time when
working on new challenges before the flow of inspiration
starts flowing. However I've seen this flow of inspiration
starting to come now, so the fruit of our joint work is
starting to bear fruit. I now have a much better understanding
of MySQL Server performance than I used to have. I know fairly
well where the bottlenecks are and I've started looking
into how they can be resolved.

Another interesting thing with Sun is the innovations they have
done in a number of areas. One such area is DTrace. This is a …