Category Archives: MySQL

Love your Free Ride entries; Keep them coming!

So far we have received 16 entries for the Proven Scaling Free Ride to MySQL Conference and Expo 2007, which will be in Santa Clara, California, April 23-26. (A recap: We are providing free airfare, hotel, meals, and a full conference pass to three people who impress us with their submissions.) A few of the submissions so far have had the panel laughing hysterically (and we DO appreciate a bit of humour in our judging). A few of you have not tried at all. I thought I’d provide some tips on what helps and what hurts as you submit your entries:

  • Helps: Showing that you have a sense of humour, and can tell a good story.
  • Hurts: Leaving all of the entry blanks empty.
  • Helps: Showing some humility, and that you will appreciate the free ride.
  • Hurts: Not knowing what the conference is about.
  • Helps: Telling us a little about how you intend to spend your time at the conference if you are chosen.

Submit your entry today! The deadline is this Friday, March 23rd at midnight PDT (GMT-7)!

Want a free ride to MySQL Conference & Expo?

Proven Scaling will sponsor three people to attend the MySQL Conference and Expo 2007 in Santa Clara, California, April 23-26!

That’s right, we will pay for your airfare and hotel, transport from the airport, and even a stipend for meals! MySQL AB has graciously provided us with conference passes for the Free Ride winners, so the winners will each receive a full conference pass.

Go to Proven Scaling Free Ride to enter. The deadline is midnight PDT (GMT-7), Friday March 23rd (just over a week away), so do it soon!

I look forward to reading your entries — and I hope to see you there!

Now Available: Profiling in MySQL

Back around November 2005, I started working on query profiling in MySQL via the SHOW PROFILE and SHOW PROFILES commands. It’s been an interesting ride, but profiling support is finally available in public releases of MySQL starting with MySQL Community 5.0.37!

I had a few thoughts on the process and the feature that I’d like to share:

It’s been rough — Although everyone at MySQL who had seen the patch had wildly positive feedback about it, it took almost a year and a half to get things committed. Chad Miller took up my cause (back in December?) with the profiling patch as well as many others, and things actually started making progress. Thanks Chad!

Things were changed — In order to accept the feature, MySQL wanted a few things changed, which Chad handled. An interface using INFORMATION_SCHEMA was added, which I don’t entirely agree with, and the times and statistics returned were changed to absolute instead of cumulative. More on this below.

Absolute times are misleading — With SHOW PROFILE you will see rows like this:

| query end            | 0.00028300 |

Does that mean it took 0.283ms to end the query? Not necessarily. The only way SHOW PROFILE knows when to cut off the timer is when the status next changes. Since the status messages were only meant to be informational, and in fact many of them were never meant to be seen in the first place, the status is not always changed in logical places in order to collect accurate timestamps this way.

My original patch only used cumulative numbers—they don’t imply any given amount of time spent in a particular place, just the total time or statistics collected at the moment the status was changed. I may submit a patch to once again reveal this information with e.g. SHOW CUMULATIVE PROFILE, as it seems very unlikely that the powers that be will allow it to be changed now.

Status messages need some updating — The last phase of the profiling patch that has yet to be done is to go through all of the status messages, cleaning them up where appropriate, and adding new messages to display more useful profiles. Perhaps I will have time to work on this soon.

Let me know how you like profiling and if you manage to make use of it!

Jeremy 2.0: Liam Alexander

Exciting news! Adrienne is resting and I hold in my arms (typing this with one hand): Liam Alexander Cole, born on Friday, March 2nd at 15:31 PST (GMT-0800). He weighs 7 lbs 11.5 oz (3501 g) and is 18.75 inches (47.6 cm) long/tall.

Sorry for miscategorizing this in the “MySQL” category — I wanted everyone to see it even if they just follow me through Planet MySQL!