July 30, 2014

8 common (but deadly) MySQL operations mistakes and how to avoid them

January 22 I gave a presentation on “How to Avoid Common (but Deadly) MySQL Operations Mistakes” for Percona MySQL Webinars. If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions. I answered as many as we […]

Followup questions to ‘What’s new in Percona XtraDB Cluster 5.6′ webinar

Thanks to all who attended my webinar yesterday.  The slides and recording are available on the webinar’s page.  I was a bit overwhelmed with the amount of questions that came in and I’ll try to answer them the best I can here. Q: Does Percona XtraDB Cluster support writing to multiple master? Yes, it does.  However, […]

MySQL performance optimization: Don’t guess! Measure with Percona Cloud Tools

In our practice we often see that MySQL performance optimization is done in a sort of “black magic” way. A common opinion is: “If there is a performance problem – then it must be a database issue, because what else could it be? And if this is a database issue, then it must involve IO […]

MySQL server memory usage troubleshooting tips

There are many blog posts already written on topics related to “MySQL server memory usage,” but nevertheless there are some who still get confused when troubleshooting issues associated with memory usage for MySQL. As a Percona support engineer, I’m seeing many issues regularly related to heavy server loads – OR OOM killer got invoked and […]

Percona XtraBackup 2.1.7 is now available

Percona is glad to announce the release of Percona XtraBackup 2.1.7 on January 24th, 2014. Downloads are available from our download site here and Percona Software Repositories. This release is the current GA (Generally Available) stable release in the 2.1 series. Percona XtraBackup is an open source, free MySQL hot backup software that performs non-blocking […]

InnoDB file formats: Here is one pitfall to avoid

UPDATED: explaining the role of innodb_strict_mode and correcting introduction of innodb_file_format Compressed tables is an example of an InnoDB feature that became available with the Barracuda file format, introduced in the InnoDB plugin. They can bring significant gains in raw performance and scalability: given the data is stored in a compressed format the amount of […]

2 cases for MySQL server overload

Your MySQL server is overloaded. You see hundreds of running queries in the SHOW PROCESSLIST taking many seconds to run, or can’t connect at all because all connections slots are busy. If you have worked with MySQL long enough you surely have seen it, probably more than once. This is what I would call “MySQL […]

Seconds_Behind_Master fluctuating wildly? Check for events caught in a loop

Recently I was working with a customer where we noticed that Seconds_Behind_Master fluctuating from an expected value of 0 seconds behind to a fairly high six figure value.  The servers were configured in a master-master relationship and used 5 figure server_id values, and we had just migrated this cluster from one data centre to another […]

Percona XtraDB Cluster 5.5.34-23.7.6 is now available

Percona is glad to announce the release of Percona XtraDB Cluster 5.5.34-23.7.6 on November 4, 2013. Binaries are available from the downloads area or from our software repositories. Bugs Fixed: Fixed the issues with upgrade on Debian caused by debian-start script. Bug fixed #1112363. Adding the AUTO_INCREMENT column to a table would result in data […]

Taking backups on Percona XtraDB Cluster (without stalls!)

I occasionally see customers who are taking backups from their PXC clusters that complain that the cluster “stalls” during the backup.  As I wrote about in a previous blog post, often these stalls are really just Flow Control.  But why would a backup cause Flow control? Most backups I know of (even Percona XtraBackup) take […]