After publishing in May a benchmark report about InnoDB Dirty pages & Log size impact I received several very interesting comments, and one of them pointed to the purge lag problem and InnoDB innodb_max_purge_lag parameter created specially for such purpose! So, I was very curious to know how it may help me in my workload...

The following study is about how innodb_max_purge_lag is working now and what may be done to make things better :-))

I'm not pretending here on any absolute truth :-) My goal is to understand what's going on with purge on my workload and see if there is something else possible to improve..

Benchmark scenario

My benchmark scenario will be exactly the same as …

MySQL Administrator's Bible

MySQL Administrator’s Bible by Sheeri K. Cabral and Keith Murphy, 2009. Page count: 800+ pages. (Here’s a link to the publisher’s site.)

This book is a comprehensive reference guide to MySQL that’s accessible to beginning DBAs or DBAs familiar with another database. It has enough detail to be a useful companion throughout a DBA’s career. It also covers many related technologies, such as memcached, at a moderate-but-useful level of detail. This isn’t exactly a how-to book, and it isn’t exactly a reference manual; it’s more of a blend of the two.

The …

It was a long run and I'm sure it felt like an eternity for many - for me it certainly did. PHP 5.3 was branched of over two years ago and finally is ready to be called 5.3.0.

The php.net website and many other blogs discuss the features - from often loved closures, to well discussed namespaces to the sometimes hated goto - so I think I don't have to this here but instead can focus on that what really matters:

• Thanks to all the developers - Without them no new features would be there.
• Thanks to the documentation team - Without them one would have to decipher the NEWS file and guess what exactly is meant.
• Thanks to all participants during the Testfest! - During the Testfest we received many good tests for our regression test suite. Many of these tests represent what people do, not what developers think they should do which is important to …

1. Set this variable
thread_stack = 265K

2. Execute this query
mysql> SELECT 0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
…

1. Set this variable
thread_stack = 265K

2. Execute this query
mysql> SELECT 0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+
0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0
…

FISL 2009 wrapped up over the weekend. Even though the conference officially ended on Saturday but the connections made there will certainly allow us to continue all the great momentum. The conference celebrates open source and it was certainly great to see Federal Government and Banks with their booths in the exhibitor halls. The visit by Brazilian President Lula certainly highlights the importance of this conference to the local community. There were booths from Debian, Firefox, Ubuntu and other major open source softwares. Some commercial vendors had a booth as well and of course Sun Microsystems had a big presence with GlassFish, Open Solaris, NetBeans, MySQL and …

The PHP BBQ tour 2009 is over. Some 145 people came to 7 meetings held in 7 different citties in Germany. The basic idea of having a series of barbecues, shortly before midsummer, to get together and having fun at a very relaxed atmosphere has worked out well.

People got connected. Some attendees came to the PHP user group meetings, who have never been seen at a regular meeting before. Some even travelled 1.5 hours per way to get to the events. Members of the user group Köln/Bonn took the opportunity to visit their friends in Dortmund and members of the user group Stuttgart have travelled to Karlsruhe for the first time.

People had fun. Look at the faces of those who came to the events, check out the photos. Due to bad weather conditions and rain showers there have been only two true BBQs. However, the BBQ …

The PHP BBQ tour 2009 is over. Some 145 people came to 7 meetings held in 7 different citties in Germany. The basic idea of having a series of barbecues, shortly before midsummer, to get together and having fun at a very relaxed atmosphere has worked out well.

People got connected. Some attendees came to the PHP user group meetings, who have never been seen at a regular meeting before. Some even travelled 1.5 hours per way to get to the events. Members of the user group Köln/Bonn took the opportunity to visit their friends in Dortmund and members of the user group Stuttgart have travelled to Karlsruhe for the first time.

People had fun. Look at the faces of those who came to the events, check out the photos. Due to bad weather conditions and rain showers there have been only two true BBQs. However, the BBQ …

I’ll be heading back to my home state (Maine) this week for a visit, and while I’m back there Patrick Galbraith and I will be talking at the Boston MySQL Meetup Group on Monday night about Drizzle, Gearman, and how to combine the two with projects like Narada. If you are in the Boston area, be sure to check it out!

Earlier I reported about two crashes related to MySQL 5.0.22 on Ubuntu 6.06 LTS.

I think those bugs show a lack of testing on the side of Cannonical/Ubuntu. And for MySQL there is a quite good test suite available, so it's not rocketsience.

There are multiple reasons why you could use the MySQL Test Framework:
1. Test if bug you previously experienced exists in the version you are using or planning to use.
2. Test if configuration changes have a good or bad result on the stability of mysqld.
3. Test if important functions still return the correct results (especially importand for financial systems)

$ echo "SELECT @@version;" > version.test
$ cp version.test version.result
$ mysql < version.test >> version.result
$ mysqltest --result-file=version.result …