October 31, 2014

Read/Write Splitting with PHP Webinar Questions Followup

Today I gave a presentation on “Read/Write Splitting with PHP” for Percona Webinars.  If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions.  I answered as many as I could during the session, but here are […]

How to obtain the “LES” (Last Executed Statement) from an Optimized Core Dump?

Ever ran into a situation where you saw “some important variable you really needed to know about=<optimized out>” while debugging?

Percona Server 5.5.18-23.0: Now with Group Commit!

Percona is glad to announce the release of Percona Server 5.5.18-23.0 on December 19th, 2011 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.18, including all the bug fixes in it, Percona Server 5.5.18-23.0 is now the current stable release in the 5.5 series. All of Percona ‘s software is open-source and free, all the details of the release can […]

Fishing with dynamite, brought to you by the randgen and dbqp

I tend to speak highly of the random query generator as a testing tool and thought I would share a story that shows how it can really shine. At our recent dev team meeting, we spent approximately 30 minutes of hack time to produce test cases for 3 rather hard to duplicate bugs. Of course, […]

The two even more fundamental performance metrics

In a recent blog post, I wrote about four fundamental metrics for system performance analysis. These are throughput, residence time, “weighted time” (the sum of all residence times in the observation period — the terminology is mine for lack of a better name), and concurrency. I derived all of these metrics from two “even more […]

Percona Server 5.1.51-rel11.5

Percona Community, Percona Server version 5.1.51-rel11.5 is now available for download. The main purpose of this release is to update the current Percona stable release to the latest version of MySQL 5.1. Functionality Added or Changed  Percona Server 5.1.51-rel11.5 is now based on MySQL 5.1.51.  New Features Added: None  Other Changes: None Bugs Fixed  Bug […]

Recall of Percona Server 5.1.47-11.0

Percona Server release 11.0 which we announced few days ago unfortunately was released with a bug introduced while implementing stripping comments in query cache which could cause server crash with certain types of queries if query cache is enabled. We have released Percona Server release 11.1 which includes a fix for this issue. If you […]

Percona Server 5.1.47-rel11.0

Dear Community, Percona Server version 5.1.47-rel11.0 is available for download now. The changes in this release include: New features Percona Server is now based on MySQL 5.1.47, and XtraDB is now based on InnoDB plugin 1.0.8. XtraDB now uses the fast recovery code released in InnoDB Plugin version 1.0.8, instead of Percona’s earlier fast-recovery code. […]

On Good Instrumentation

In so many cases troubleshooting applications I keep thinking how much more efficient things could be going if only there would be a good instrumentation available. Most of applications out there have very little code to help understand what is going on and if it is there it is frequently looking at some metrics which […]

How number of columns affects performance ?

It is pretty understood the tables which have long rows tend to be slower than tables with short rows. I was interested to check if the row length is the only thing what matters or if number of columns we have to work with also have an important role. I was interested in peak row […]