One of the cooler things has been worked on in libmemcached lately is the ability to tinkertoy up Memcached servers.

What does that mean?

There are a lot of forks of memcached. Some commercial, some open source, some that are in house at a variety of companies. They all share a few common concepts though.

Protocol
Scale Out

The recognition of this lead me to want to create a set of libraries that anyone, could use to build these types of servers quickly. After talking to a number of vendors and users it became pretty apparent that something like this needed to be done. The goal is to make it easy for people to write protocol compatible servers in a way that they can focus on the …

I had trouble today on a client site using my MySQL power tools Maatkit and Statpack.

$ ~/scripts/statpack.py --files=mysql.status.091015.080001.txt,mysql.status.091015.090001.txt
Traceback (most recent call last):
  File "/home/rbradfor/scripts/statpack.py", line 563, in ?
    main()
  File "/home/rbradfor/scripts/statpack.py", line 527, in main
    locale.setlocale(locale.LC_NUMERIC, '')
  File "/usr/lib64/python2.4/locale.py", line 381, in setlocale
    return _setlocale(category, locale)
locale.Error: unsupported locale setting

$ cat /var/log/slow-query.log | ./mk-query-digest
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
        LANGUAGE = (unset),
        LC_ALL = (unset),
        LANG = "e_US"
    are supported and installed on your system.
perl: warning: Falling back to the standard …

Installing Apache2 With PHP5 And MySQL Support On OpenSUSE 11.1 (LAMP)

LAMP is short for Linux, Apache, MySQL, PHP. This tutorial shows how you can install an Apache2 webserver on an OpenSUSE 11.1 server with PHP5 support (mod_php) and MySQL support.

A client recently asked me to fix some Cacti graphs that had broken after upgrading the Cacti templates I wrote for MySQL. The symptoms were weird; I’m not sure I understand fully what happened, but some of the graphs were OK and some had only part of the data they were supposed to. Some graphs would have one data element as usual, and others would be nan (not a number).

After turning on the debug logs, I found that the script was returning the data correctly — it was not a script problem. But after Cacti got the data from the script, it wasn’t associating it correctly with the RRD archives. Here’s a log message:

10/14/2009 12:05:05 PM - CMDPHP: Poller[0] Host[11] DS[1270] CMD: /usr/bin/php -q
  /opt/cacti/scripts/ss_get_mysql_stats.php --host dbserver
  --items bj,bm --user --pass , output: bj:68 bm:64
10/14/2009 12:05:05 PM - CMDPHP: Poller[0] DEVEL: …

Here’s a quick flowchart for the different ways that Kontrollbase gathers and processes data.

In addition to the Spider engine, Kentoku SHIBA has also created the …

OpenSQL Camp Portland 2009 is coming up on the 14th and 15th of November. Eric Day (of the Drizzle project) is the lead organiser this time around.

I went to the first edition in Charlottesville VA last year which was organised by Baron Schwartz (Percona). It was a great event, like other unconferences but with specific focus on database technologies. Monty (MySQL), Brian (Drizzle), Richard (SQLite), Jim (Interbase/Firebird/Falcon), Bruce (PostgreSQL) were all these, as were various storage engine builders. Very interesting, and lots of informal fun. If you’re anywhere near, do go!

Even though noone from our gang is able to make it to this one, Open Query is sponsoring this event – for all the above reasons. It rocks and deserves every support.

At Days of Wonder we are huge fans of MySQL (and since about a year of the various Open Query, Percona, Google or other community patches), up to the point we’re using MySQL for about everything in production.

But since we moved to 5.0, back 3 years ago our production databases which hold our website and online game systems has a unique issue: the mysqld process uses more and more RAM, up to the point where the kernel OOM decide to kill the process.

You’d certainly think we are complete morons because we didn’t do anything in the last 3 years to fix the issue

Unfortunately, I never couldn’t …

– Arjen Lentz, Exec.Director @ Open Query (http://openquery.com) Exceptional Services for MySQL at a fixed budget. Follow our blog at http://openquery.com/blog/ OurDelta: enhanced builds for MySQL @ http://ourdelta.org

Just a reminder – BarCamp Brisbane is on again this Saturday, all day, at the East Brisbane Bowls Club. Its a chance for techies and tech entrepreneurs to get together and meet each other, swap knowledge and ideas, and perhaps start new and exciting ventures. If you’re interested in coming along, please sign up and RSVP!

Open Query sponsors this event, together with lots of other locally-based businesses. From previous editions, I know it’s an excellent day, you always learn new things about unexpected topics!

For the my previous post, there was comment to suggest to test db_STRESS benchmark on XtraDB by Dimitri. And I tested and tuned for the benchmark. I will show you the tunings. It should be also tuning procedure for general heavy writing workloads.

At first, <tuning peak performance>. The next, <tuning purge operation> to stabilize performance  and to avoid decreasing performance.

<test condition>

Server:
PowerEdge R900, Four Quad Core E7320 Xeon, 2.13GHz, 32GB Memory, 16X2GB, 667MHz

db_STRESS:
32 sessions, RW=1, dbsize = 1000000, no thinktime

XtraDB: (mysql-5.1.39 + XtraDB-1.0.4-current)
innodb_io_capacity = 4000
innodb_support_xa = false
innodb_file_per_table = …