The latest from the MySQL community

Personally, I’m not a fan of more than one ndbd per machine…

Diamond Notes » Fun with Running a Cluster on Two Servers

Others might argue with this, but I would never put the SQL nodes on the same servers as the ndbd nodes for production. Some say you can run multiple ndbd nodes on the same server and I am more comfortable with that since I can lock the ndbd daemon into memory and know its not going to change (my ndbd nodes on those two servers have been at exactly 71.3% since I started them up. If I had servers for the ndbd nodes that had 16+ gigs of RAM I might start allocating 4 gigs of RAM to a ndbd daemon with 3+ daemons per node. My understanding is that this helps keep the transactional logs for the nodes under control. When you do a ndbd node restart it takes less time for a node to get up and running because of the …

By Tim O'Reilly

Maker Faire Austin is in full swing. I'm not there, having just finished up the Web 2.0 Summit in San Francisco, recuperating at home before heading out Monday for a MySQL board meeting in London, but I'm watching the goings-on via Flickr, at home via my chumby. Chumby is a streaming media device that replaces the old clock radio. You can configure it with all kinds of flash widgets -- great for ambient information. They also support a "virtual chumby" so I can share with you what I'm watching now. Right now, I've got it set to Scott Beale (laughingsquid)'s flickr photo stream from Maker Faire Austin:

Update: As Scott wasn't adding more photos as quickly as I …

Our Web team has just installed the newest Wordpress MU edition for blogging, and Akismet for spam fighting — plus a new layout. I’m already relieved from lots of spam, which feels great!

I’d like to make a couple of remarks on the banner, which has pictures by my two favourite portrait photographers, James Duncan Davidson and Julian Cash.

The two leftmost pictures are by Duncan, from panels at the last two MySQL Users Conferences. The first one is from the Clash of the DB Egos at the MySQL Conference and Expo 2007 (no, I am not chewing my nails or eating sweets — I am blowing a whistle to keep the egos apart), and the second one from the 2006 conference panel interviewing the MySQL …

As indicated last week, we have decided to start producing a condensed report of outstanding issues in our current development release, MySQL 5.1.

This list is now available as part of our reference manual at dev.mysql.com/doc/refman/5.1/en/open-bugs.html.

The list is updated daily based on the then-current status in our bug database.

The purpose of the list is to make it possible for our users to more easily make an informed judgement about whether our development release is ready for them to test and use. While the corresponding bugs have already been openly and publicly available for searching in our bug …

As I wrote a few days ago, I'm writing the replication chapter for the second edition of High Performance MySQL. I'm writing about replication filtering rules right now, and I thought it would be good to get input on this. If you have favorite replication filtering tricks you'd like to share, or tasks that always frustrate and/or confuse you, please post them in the comments. I'm making a section that shows how to accomplish common filtering and rewriting needs, such as preventing GRANT statements from replicating to the slaves.

Thanks very much! I hope the community involvement will make this book more useful for everyone.

Last night I prepared a Debian package of MySQL Proxy. It still lacks an init script and a manpage, but beside that it works fine. I plan to finish and upload the package to unstable within the next days.

For details about using MySQL Proxy read Getting Started with MySQL Proxy by Giuseppe Maxia.

So, at midnight I got a call from customer service saying our site was slow. I narrowed it down to one of our auxiliary databases, that seems to have gotten wedged just about midnight. Normal queries that took less than 4 seconds started taking longer and longer, moving up to 5 seconds and past 30 seconds in the span of a minute or so.

In the moment, I thought killing off all the queries would be a good move. My kill script, which consists of:


for i in `/usr/bin/mysql -u user -pPass -e ’show full processlist’ | grep appuser | cut -f1`
do
mysql -u user -pPass -e “kill $i”
done


This will attempt to kill any mysql connection owned by the appuser. I used it a few times, and it didn’t work. So I used a trick I learned when we bring our site down — sometimes there are straggling connections to mysql, so what I do is change the app user’s password by direct …

As I wrote a few days ago, I’m writing the replication chapter for the second edition of High Performance MySQL. I’m writing about replication filtering rules right now, and I thought it would be good to get input on this. If you have favorite replication filtering tricks you’d like to share, or tasks that always frustrate and/or confuse you, please post them in the comments. I’m making a section that shows how to accomplish common filtering and rewriting needs, such as preventing GRANT statements from replicating to the replicas.

Yesterday I visited the MySQL Customer Conference in Munich. First of all, GDL sucks. But the locomotive driver strike was the only negative issue on that day, the conference itself was quite good, especially Jan Kneschke's talk about MySQL performance tuning (which was mostly about combining MySQL Cluster and MySQL Proxy) and the panel discussion about storage engines with Ralf Gebhardt, Jan Kneschke and Kai Voigt as vocal and Kaj Arnö as moderator. All in all a great (but quite long and exhausting) day.

Beta or not, here we come. Yea, you'd think I'd learn to check out the known bugs list before letting developers/qa have at the new database servers running in the lab with MySQL 5.1.21-b . I mean, how bad could beta really be?Well, as we should all know, beta is called beta for a reason, but sometimes we open source fanatics tend to jump on board, dealing with issues along the way. This