After a discussion with my colleague Stephane Varoqui we decided to see how Gearman and the NDBAPI could be used together. The result of the POC was a Gearman worker and a couple of clients (clients and workers use Google Protocol Buffers as the protocol). The worker can:

• set/get/delete records on a single table in MySQL Cluster using the primary key
• set/get/delete "any" type. It is not possible to dynamically add types but this is done at compile time.
  
• supports the following SQL data types: (UNSIGNED) INTEGER, (UNSIGNED) BIGINT, CHAR, VARCHAR/VARBINARY
• support the following Google Protocol Buffer …

The big number of Ubuntu bugs can sometimes be overwhelming. Providing high quality bugs can help in getting the bugs triaged and fixed faster. This is where Apport comes into the game – a tool used to automatically generate crash reports for debugging. Apport can be extended via hooks to provide specific information on a per package basis. For example the Ubuntu Server team added hooks for MySQL during the Karmic release cycle. Relevant logs as well as configuration information are automatically added to every bug reported against the mysql package.

If you have ideas about adding apport hooks for other server related packages let the Ubuntu Server team know. Add it to the wiki page, look up how to write apport …

　一昨日に開催された hbstudy #7 にバックアップの話を聞きに行ってきました。Amanda を中心にした話で、とても勉強になりました。が、設定がめんどくさそうだなぁ、とも。自分の需要にはあわない感じでした。

　勉強会が終わったあとで、自作のバックアップスクリプト blockdiff に関する話を何人かの方とさせていただいたのですが、思いのほか反応が良かったので、あらためて紹介したいと思います。

　blockdiff は、一言でいうと、パーティションやデータベースのデータファイルの差分バックアップツールです。rsnapshot に似ていますが、rsnapshot …

We have now released MariaDB 5.1.41 RC for download and testing. You can download it here. It should be a drop in replacement for any recent MySQL 5.1 release.

We currently have tar archives available and we should have many package formats available shortly.

MariaDB 5.1 is based on MySQL 5.1 codebase, which has been GA for a year now. Most of the things we have included in addition to the vanilla 5.1 code upstream from Sun/MySQL (more on this below) have also been available in the community for quite a long time, so we are quite confident that this is a very stable release; however, being conservative we have had a four month Beta cycle before now going to RC.

I would now like to invite everyone in the community to download and test this release, and if the feedback is good will we then rapidly release a Final …

I’ll be speaking at the data retrieval miniconf at Linux Conference in Wellington, New Zealand (Full Text Search with MySQL, Program)
I’ll cover some new sphinx search features (online updates)

Question: How can you select records from one table that doesn’t have a specific ID in a second, many-to-many table?   In other words, imagine you have a questions table (A), categories table (B), and a many-to-many relationship link table (L).  This setup allows a question to have several categories.  How can you find questions that […]

Never have I planned a program so much in detail before starting coding. And stranger still, I’m planning the program to be coded in a language in which I haven’t written a single line of code. Nonetheless, I’m eager and it feels good.

I woke up early this Sunday, my mind concentrating on the many steps I will have to take before the first project will see the light of day. I had planned eight prerequisite lessons before even starting the coding. And despite receiving many good pieces of advice, nobody had relieved me of my main worry — the input grid for the data entry in matrix format.

To speed up things, I thought of writing some auto-generated INSERT statements from the current Google Spreadsheet that I’ve been using. I would then at least have the basic data from the first two weeks of the year to play around with in my MySQL database.

And then it struck me: I don’t need a grid at …

Over the last couple of months I have run into a number of replication problems where I needed to run reports on MySQL binlogs to understand what sort of updates servers were processing as well as to compute peak and average throughput.   It seems that not even Maatkit has a simple tool to report on binlog contents, so I wrote a quick Perl script called analyze-binlog.pl to summary output from mysqlbinlog, which is the standard tool to dump binlogs to text. 

The script operates as a filter with the following syntax:

Usage: ./binlog-analyze.pl [-h] [-q] [-v]
Options:
  -h : Print help
  -q : Suppress excess output
  -v : Print verbosely for debugging

To get a …

In the Autumn, I wrote about some experiments I did using KVM and virtual machines to build and test MariaDB binary packages on a number of different platforms. In the period since then I added some polish and refinements, and the system is now running well for some time. We build and test packages for Debian (4 and 5), Ubuntu (8.04 to 10.04), Centos 5, and generic Linux; amd64 and i386 architectures.

To better control the startup and shutdown of the virtual machines, I created a small wrapper script around KVM called runvm. This wrapper encapsulates the steps needed to boot up a virtual machine, run a series of commands inside it, and shut it down gracefully afterwards. Some special care is taken in the script to ensure that the …

I generally thought about MySQL replication as being quite low overhead on Master, depending on number of Slaves. What kind of load extra Slave causes ? Well it just gets a copy of binary log streamed to it. All slaves typically get few last events in binary log so it is in cash. In most cases having some 10 slaves are relatively low overhead not impacting master performance a lot. I however ran into the case when performance was significantly impacted by going from 2 to 4 slave on the box. Why ?

The reason was Master was having a lot of very small updates going on - over 15.000 transactions a second. Each time event is logged to the binary log all 4 threads feeding binary logs to the slave were to be woken up to send the update notification. With 4 slaves connected this makes 60.000 of threads being woken up sending some 60.000 packets (there may be some buffering taking place on TCP side merging multiple sends but still)

I guess …