This week saw the release of OurDelta patchset d7 build of MySQL 5.0.67, basically a cleaned-up update of the earlier (and first) OurDelta d6 build. The number of downloads/fetches within the first few hours surpassed the total number from the previous weeks.

Downloads and yum/apt-get repository fetches now always go via one of our mirrors, as obviously the main server can’t possibly handle all that attention! By default you just get sent to “somewhere on the planet”, although you can tweak your repo setup to only use specific mirrors. If you want to become a mirror for OurDelta, drop us a line and we’ll be happy to add you in; the more the merrier!

Ubuntu 8.10 Intrepid is now also supported. We welcome input on which additional platforms are desirable.

There was a  …

In 2 years (ish):

• the majority of consumer bought machines (which will be laptops) will have SSD and not rotational media
• At the same time, servers with larger storage requirements will use disk as we once used tape.
• At least one Linux distributoin will be shipping with btrfs as default
• OpenSolaris will be looking interesting and not annoying to try out (a lot more “just work” and easy to get going).
• Unless Sun puts ZFS under a GPL compatible license so it can make it into the Linux kernel, it will become nothing more than a Solaris oddity as other file systems will have caught up (and possibly surpassed).
• There will be somebody developing a a MySQL compatible release based off Drizzle
• Somebody will have ported Drizzle back to Microsoft Windows… possibly Microsoft.
• X will still be used for graphics on Linux, although yet another project will …

James Purser of Open Source on the Air has done a podcast interview with Arjen Lentz about OurDelta, describing it as “a new distro for MySQL”.

The maximum length of a VARCHAR is only restricted by the maximum row length. In most storage engines, the maximum row length is the maximum allowed by MySQL, which is 65,535 bytes. Only the NDB storage engine has a different maximum value.

The VARCHAR data type has some overhead. If the length of VARCHAR is less than 255, one byte per row is used to store the actual length of the string. If the length of VARCHAR is greater than 255, the overhead cost of storing the string length is two bytes per row. Thus, the maximum length of a VARCHAR should be 65,533 bytes.

However, that is not the case:

mysql> CREATE TABLE max_len_varchar(fld VARCHAR(65533) CHARSET latin1);
ERROR 1118 (42000): Row size too large. The maximum row size for the used table type, not counting BLOBs, is 65535. You have to change some columns to TEXT or BLOBs

mysql> CREATE TABLE …

I had this perplexing problem yesterday where a mysql dump and restore was producing different results when using MaatKit mk-table-checksum.

mk-table-checksum --algorithm=BIT_XOR h=192.168.X.XX,u=user,p=password --databases=db1 --tables=c
DATABASE TABLE   CHUNK HOST         ENGINE      COUNT         CHECKSUM TIME WAIT STAT  LAG
db1      c           0 192.168.X.XX InnoDB     215169         d1d52a31    2    0 NULL NULL
mk-table-checksum --algorithm=BIT_XOR h=localhost,u=user,p=password --databases=db1 --tables=c
DATABASE TABLE   CHUNK HOST      ENGINE      COUNT         CHECKSUM TIME WAIT STAT  LAG
db1      c           0 localhost InnoDB     215169         91e7f182    0    0 NULL NULL

It was rather crazy until I reviewed the mysqldump settings I was using, and I realized I was using –no-set-names.

So just what does this option remove. Here is a diff of mysqldump with and without.

He started talking …

We’ve packaged another alpha-version of our current work-in-progress version of workbench - version 5.1.4. We’ve added more features, fixed problems and started to build packages for Fedora Core 9 along with our binaries for Ubuntu 8.04.

MySQL Workbench OSS 5.1.4 Alpha - Linux

Source Tar Ball

ftp://ftp.mysql.com/pub/mysql/download/gui-tools/mysql-workbench-5.1.4alpha.tar.gz
ftp://ftp.mysql.com/pub/mysql/download/gui-tools/mysql-workbench-5.1.4alpha.tar.gz.md5

Binaries for Fedora Core 9

…

The Idea.

For the past month I have been exploring options and building a perfect Home Theater PC for my 50” Vizio plasma. Besides the obvious, it has to play movies, youtube videos, etc, I had a few concrete goals in mind. Here they are:

• it absolutely had to handle 1080P h264, specifically movies encoded using x264. An average movie size for this format is between 8.5 and 13 GB. There were 2 problems to overcome: the CPU had to be able to handle the decoding (my desktop dual core Conroe barely kept up) and the network had to be fast enough to stream in real time from my storage PC a floor away.
• I needed to have the easiest control over the whole thing. VNC wasn’t good enough, because I don’t always have a laptop lying around.
• It had to support 7.1 sound.
• It had to have excellent picture quality on the TV, preferably during both movies and regular browsing/reading, etc. HDMI/DVI was …

In case anyone is interested in a copy of my slides for the two lightning talks I gave at the Open Source Days 2008 conference, I have made them available here:

• "Optimizing Large Databases Using InnoDB Clustered Indexes:" HTML and PDF.
• "Profiling with OProfile and Intel Core 2 performance counters:" HTML and PDF.

I waqs quite pleased with the benchmark that I prepared for the InnoDB mini-talk, where I measure the performance …

We have finished the next release of MySQL Workbench 5.0 GA, 5.0.27. It features a number of bugs fixed, especially in the synchronization code, a huge improvement in terms of memory usage and an updated layer-pane, listing all objects on a diagram-canvas - now including conections too (this allows easy selection of hidden objects). Use the Update-function from the help menu or head over to the download pages to get your copy:

http://dev.mysql.com/downloads/workbench/5.0.html

Please let us know if bigger models now load faster and if you are seeing an improved performance of the canvas.