When I worked with Dimitri on the analysis of the
Split Rollback Segment Mutex he came up with numbers
on InnoDB Thread Concurrency set to 16 and 32 and I was curious
to see if 24 was the optimal setting. So he made some new runs and
some new graphs that I found interesting.

The first graph analyses behaviour of MySQL 5.4.0 on a SPARC
Server using InnoDB Thread Concurrency set to 0, 16, 24 and 32.
Interestingly for both readonly and readwrite benchmarks the
optimal setting for concurrency is 16 whereas the top numbers
(at 32 threads) is achieved with concurrency set to 24 or 32.



…

Sometimes I miss the coding I did last century. Today I was reminded of some of the fun, when I had set my mind to doing some statistics on my blogging.

In a blog entry on http://blogs.arno.fi/isit/2009/05/14/home-made-blog-statistics-from-wordpress-mu/ I describe what I did.

The blog entry may be of interest for those who use WordPress and are set back by the huge amounts of tables it generates. I happen to host 18 blogs and with each blog requiring 8 tables, that’s a total of 144 tables. Add the 9 top-level blogs and I’ve got 153 tables to navigate.

The blog entry I wrote 

• identifies the key fields
• shows how to …

When I read the blog about Split Rollback Segment Mutex,
I was interested to verify those results in the context of MySQL 5.4.0.

The patch can be found here.

We've analysed this patch both on a large SPARC system and on my
benchmark x86/Linux machine. Our results tend to be positive for
readwrite benchmarks but sometimes negative for readonly
benchmarks. Also the gain is much smaller than found in the
blog.

Also this patch has two negative effects, the first is that it
provides an upgrade problem, this can probably be handled in the
InnoDB code, but requires quite some digging. The other is that
instead of writing UNDO results to one UNDO log, we write …

Now that installing MySQL in Solaris zones is even officially supported by the MySQL support group (see http://www.mysql.com/about/legal/supportpolicies/policies-06.html#q03), the question is: What is the right way of installing MySQL in a zone. Of course this depends on what you want to achieve. The following description is based on Solaris 10. On Opensolaris this is different (somewhat easier, as there are no more sparse root zones.)
If you run a local zone as a whole root zone, you can easily install MySQL from tarball or the package installer.
If you run a local zone as a sparse root zone, there are different options:
First you cannot use the package installer, as this procedure will copy binaries to /usr/bin. But /usr/bin is inherited from the global zone and write protected. You have to use the tarball installation. …

At http://trubix.blogspot.com I've written a blog on the importance of peripheral DBA skills. In the MySQL world, the following peripheral skills are very helpful for managing MySQL environments:LAMP skills - Linux, Apache, PHP/Perl/Python.Application Servers - knowledge of Apache, JBoss, LightHTTP, connection pooling, etc.Monitoring skills - Enterprise Monitor, Nagios, Cacti, etc.Ability to

The MySQL Administrator’s Bible is out. Writing a book is not something you can just squeeze into a Sunday afternoon; it takes real dedication and more effort than you could possibly imagine.

So congrats on having the book for MySQL DBAs (and I’d venture to say application devs should also be reading it) out and on Amazon so people can buy it now.

For the past few months, I’ve been helping my friend develop and market Philtro .
We’ve gone through various iterations of the elevator pitch for it, and the one that seems to be kinda working, is: “It’s like a spam filter for your Twitter account.”

At SXSW, I got the opportunity to talk to Guy Kawasaki about this tool, and he said “There is no spam on twitter, if you don’t like it, don’t follow them”.

While that’s an easy way to handle spam, I also realized that the word Spam means different things to different people.

On Twitter, nothing is UCE. It’s easy to block the profiles with …

A few months ago I installed ActivePerl 5.10 on a Windows XP Pro workstation. Next I tried to install DBD::mysql using CPAN, it failed. When I browsed modules via ppm, a GUI in this version of ActiveState Perl on Windows, DBD::mysql was not listed as an available module.

I then downloaded the source code, manually modified the MAKE file, fiddled with Visual Studio NMAKE, compiled it a few times, without success.

Google revealed the existence of Strawberry Perl. So I removed ActiveState Perl, installed Strawberry, ran ppm install DBI, ppm install DBD-mysql. And it worked.

Fast-forward a few weeks, I started playing with EPIC, a plugin for Eclipse that supposedly provides a nice IDE for Perl development and debugging. As a result, I started fiddling with PadWalker, a prerequisites for EPIC. I couldn’t remember all the details now due to frustration, but suffice it …

Maybe it's a sense of shared adversity, but recent MySQL meetings have had this "we're all in it together" feeling. Today Monty Widenius announced the Open Database Alliance: the community feeling is starting to look like a real business entity.

The Open Database Alliance is appealing at multiple levels. First, it's good for the companies that join--a steadier flow of business and ability to offer bigger solutions by combining with partners. Second, it's good for users: first rate software, services, and support without vendor lock-in. Third, the parties are going to be excellent.

Sometimes you have to think hard before signing up for partnerships. But this one looks like a no-brainer. Count us in!

…