We are pleased to announce the release of High Availability Cluster software for OpenSolaris 2009.06! If you've been following along, this release is the fruit of project Colorado. Open HA Cluster 2009.06 is based on Solaris Cluster 3.2, including many of the features from the most recent update. Additionally, Open HA Cluster 2009.06 contains the following new features:

• The ability to use Crossbow VNICs as …

John Albin Wilkins presents "Making Drupal Dance: Techniques for Non-obvious Theme Manipulations at the 2009 Design 4 Drupal conference in Boston. Unfortunately the beginning is cut off; however there is still over 40 minutes of video and plenty of good information in the video.

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This is mainly a cheat sheet for me to remember. Nothing rocket science.

It often makes sense to use netcat/nc to copy MySQL database between hosts in trusted networks. It bypasses encryption overhead of SSH and depending on configuration can be significantly faster.

Also note MySQL should be down when you copy data unless you're copying from snapshot etc.

So to copy go to the mysql data directory on both boxes; such as cd /var/lib/mysql . Make sure target directory is empty. Now on the TARGET server do nc -l 4000 | tar xvf - and on the SOURCE server do tar -cf - . | nc target_ip 4000

Also note - the port you're using should be open in the firewall.

Entry posted by peter | 22 comments

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Last night my residential area lost power for about 2 hours, between 2-4 am. This reminded me of something, and there’s analogies to MySQL infrastructure. Power companies have over recent years invested a lot of money in making the supply more reliable. But, it does fail occasionally still.

From my perspective, the question becomes: is it worth the additional investment for the power companies? Those extra few decimal points in reliability come at a very high cost, and still things can go wrong. So a household (or business) that relies on continuity has to put other measures in place anyway. If the power company has an obligation to deliver to certain standards, it might be more economical for them to provide suitable equipment (UPS, small generator) to these households and business (for free!) and the resulting setup would provide actual continuity rather than merely higher reliability with occasional failures. Everybody …

I’ve decided to give people two more days for a chance to win a free MySQL Book — Sheeri Cabral’s MySQL Administrators Bible.

I have had five people so far provide recommendations for a simple MySQL configuration question as stated in For MySQL DBA fame and glory. Prize included. Shlomi Noach the current front runner.

Try your MySQL Performance Tuning skills. This is a good opportunity for new MySQL DBA’s and experienced DBA’s to provide basic input.

It seems that a lot of people want to try to improve MySQL performance by focusing on server status counters and configuration variables. Looking at counters, and “tuning the server,” is better than nothing, but only barely. You care first and foremost about how long it takes to execute a query, not about how many of this-and-that the server performs or about how big or small this-and-that buffer is. What you really need is timing information.

You can use the slow query log to find timing information about queries, and then you can examine those queries with SHOW PROFILES to see the timing information about the query’s execution itself.

This concept is very simple and absolutely fundamental: if you care about time (and you do!), then measure and optimize time. But it’s so often overlooked or misunderstood.

The addition of SHOW PROFILES was a major step forward in the ability to optimize server and …

That’s the current Open Query quickpoll. Thanks.

You can also post a comment to clarify your yes/no vote, either on the poll page or here.

A bit of fun for a Sunday.  Below is the list of my top 10 interesting companies in Data Management right now.  Interesting to me means doing new stuff and being somewhat disruptive, or have a “watch and see” quality about them.  Note this is about companies not data management applications. 

While I find a bunch of other data management applications interesting (PNUTS, Cassandra, Redis etc) these aren’t really encapsulated in a company with a go to market strategy.

10gen - They are making interesting noises not sure about delivery yet
Amazon – SimpleDB is neat, but not a grown up data platform yet
Aster Data – Doing funky things with Map/Reduce
GroovyChannel – Are they nuts, they have to change …

Here's something to be aware of. The table_rows column in the information_schema.tables table does not accurately reflect the number of rows in the actual table.This weekend I was moving a db from one host to another. As a good DBA, I took the row counts from each table I was moving so I could check it on the other side. When the copy was done, I queried information_schema.tables again and

It seems that a lot of people want to try to improve MySQL performance by focusing on server status counters and configuration variables. Looking at counters, and “tuning the server,” is better than nothing, but only barely. You care first and foremost about how long it takes to execute a query, not about how many of this-and-that the server performs or about how big or small this-and-that buffer is. What you really need is timing information.