One of my slave servers stopped twice in the last couple of days. The error in the error log file was:

061214 21:17:41 [ERROR] Slave: Error 'Lock wait timeout exceeded; try restarting transaction' on query. Default database: 'fl_db1'. Query: 'UPDATE user SET total_photos = total_photos + 1 WHERE user_name = '666damy666'', Error_code: 1205
061214 21:17:41 [ERROR] Error running query, slave SQL thread aborted. Fix the problem, and restart the slave SQL thread with "SLAVE START". We stopped at log 'db2-bin.003509' position 342646547

I tried to learn more about the error code using perror and got

-bash-3.00$ perror 1205
Illegal error code: 1205

Information about the error is available on MySQL server error messages page of the manual.


…

MySQL’s user variables have interesting properties that enable the useful techniques I wrote about in recent articles. One property is that you can read from and assign to a user variable simultaneously, because an assignment can be an r-value (the result of the assignment is the final value of the variable). Another property, which sometimes causes confusing behavior, is un-intuitive evaluation time. In this post I’ll show you how to make sure your variables get updated at the time they’re used, instead of potentially reading and updating them at different stages of query execution.

In two previous posts (first here and second here) I reported about Java 5 VM crashes on Linux machines.

Digging deeper into the problem with external support led to some new evidence. Apparently the problem is in some way related to regular garbage collects initiated by the so called "GC Daemon" thread. It gets spawned when you use some fashion or other of RMI and calls full GCs in order to get rid of unreachable remote objects.

One can specify the interval (in milliseconds) between calls to the garbage collector using -Dsun.rmi.dgc.server|client.gcInterval. With our application using RMI to call remote services we reduced this value to as little as 6 seconds. As we expected this let us reproduce the problem we have much more …

In two previous posts (first here and second here) I reported about Java 5 VM crashes on Linux machines.

Digging deeper into the problem with external support led to some new evidence. Apparently the problem is in some way related to regular garbage collects initiated by the so called "GC Daemon" thread. It gets spawned when you use some fashion or other of RMI and calls full GCs in order to get rid of unreachable remote objects.

One can specify the interval (in milliseconds) between calls to the garbage collector using -Dsun.rmi.dgc.server|client.gcInterval. With our application using RMI to call remote services we reduced this value to as little as 6 seconds. As we expected this let us reproduce the problem we have much more …

The Guardian has a fantastic interview with Jeff Raikes, a senior Microsoft executive. Raikes echoes something I heard from Nick McGrath during our dinner a week ago in London - Microsoft focuses on the customer, not undermining competitors. Take that with a massive Great Salt Lake load of salt, of course, but I do think that when competing with Microsoft (or anyone), it's best to focus on the customer, not the competitor. By focusing on the competitor, you let them define the value proposition (i.e., the battleground).

A few gems from the interview:

On SharePoint...

ow there's Office SharePoint Server, which takes the server side to a new level. Bill and I would draw the analogy to when we put together the Office productivity suite in the late 80s: we think Office SharePoint Server …

mysql podcast

Episode 2 of OurSQL: The MySQL Database Podcast is here! It’s a bit late due to a computer crash and the fact that I sprained my ankle, but I think it’s worth waiting for. Particularly since this week’s feature is everyone’s favorite — performance tips!

It’s best to subscribe to the podcast by clicking the “podcast” graphic at http://www.technocation.org , or searching for “mysql” in your favorite podcast directory (including iTunes). But if you want to play episode 2 in your browser, visit http://technocation.org/index.php?option=com_content&task=view&id=22&Itemid=29

Please consider promoting the show — we have a 40 second promo ready for download at:

http://www.technocation.org/podcasts/oursql/OurSQLpromo1.mp3
Show …

From time to time I receive requests from friends who are interested in learning more about managing MySQL on Solaris 10. To help them (and myself), I am planning to write about the internals of both MySQL and Solaris.

So if you have any questions that relate to adminstering and managing MySQL on Solaris, post them as comment, and though I don't promise, I will do my best to answer them.

What I usually recommend my friends is that they should start learning by finding a good authoritative book. In my opinion, reading one good authoritative book on the subject is better than reading three normal books.

BTW, I used to spend a lot of time finding the right book before buying it. Earlier this year I signed up for Safari Books Online (by O'reilly). My membership gave me a ten slot bookshelf. I …

Very few of the times I have spoken has it been caught on tape, and
in this case it wasn't when I was trying to say something brilliant:
http://blip.tv/file/115874

This is from the http://igniteseattle.com/ event that happened in
Seattle last week. Brady should be thanked, it was a lot of fun.

A couple of thoughts:

1) I work on Apache modules, not directly Apache (and while I have
been asked to donate code I never have). Someone is likely to
nitpick, so I mention this.
2) Somehow in my head I was trying to get out "geeks who go into
basements and create incredible things". Its like the myth of Silicon
Valley inventors who go off into garages and come out with billion
dollar companies (and I don't know where Mark lived when he …

We’ve been getting some nice feedback on our recently introduced Monitoring and Advisory Service that’s part of MySQL Enterprise. In talking with many of you, I know anything that makes MySQL less of a black box with respect to what’s going on underneath the covers is welcome.

If you’re a MySQL DBA or a dev/sysadmin who’s got the responsibility of taking care of one or more MySQL servers, check out the latest article I wrote on our dev zone that highlights some things in our new service that you’ll likely find appealing. And as always, let me know what you think so we can keep making things better.

MySQL 4.0 has now reached the final stage of its active development life cycle. As I noted on 12 July 2006 when announcing the MySQL Lifecycle Policy, keeping legacy versions of our software alive is expensive and time-consuming. While we know that database administrators hate to upgrade their databases, we believe that the vast majority of our customers and our community are better served by us focusing our attention on newer releases. However, we don’t want to abandon users of our older products — so we are asking them to help subsidise the cost themselves.

This means that those who wish to continue to receive our support for MySQL 3.23 and MySQL 4.0 will need to be covered by a MySQL Enterprise subscription, starting 1 Oct 2006 for MySQL 4.0.

In …