Last night a customer had an emergency in selected machines on a large cluster of quite uniform database servers. Some of the servers were slowing down in a very puzzling way over a short time span (a couple of hours). Queries were taking multiple seconds to execute instead of being practically instantaneous. […]Read more
Preamble: On performance, workload and scalability:
MySQL has always been focused on OLTP workloads. In fact, both Percona Server and MySQL 5.5.7rc have numerous performance improvements which benefit workloads that have high concurrency. Typical OLTP workloads feature numerous clients (perhaps hundreds or thousands) each reading and writing small chunks of data. The recent improvements to […]
The new release of Maatkit has a useful feature in mk-index-usage to help you determine how indexes are used in more flexible ways. The default report just prints out ALTER statements for removing unused indexes, which is nice, but it’s often helpful to ask more sophisticated questions about index usage. I’ll use […]Read more
Before I start a story about the data recovery case I worked on yesterday, here’s a quick tip – having a database backup does not mean you can restore from it. Always verify your backup can be used to restore the database! If not automatically, do this manually, at least once a month. No, […]Read more
Based on discussions with several clients, we are strongly considering implementing a limited form of parallel replication. Single-threaded replication is one of the most severe limitations in the MySQL server.
We have a brief outline of the ideas at this wiki blueprint. So far, the “binlog order” idea is the only one that […]
Register now for a free Percona webinar about migrating your MyISAM databases to InnoDB. Save the date: Dec 1, 2010 at 9:00 AM PST (California) time.
Update: the date was originally listed as December 2nd, but that was a mistake. It’s December 1st.
We know that not everyone can attend expensive conferences that require […]
You probably saw the Twitter storm over Oracle’s pricing changes and InnoDB in the last few days. The fear about Oracle removing InnoDB from the free version of MySQL was baseless — it was just a misunderstanding. Still, in the years since MySQL has been acquired by Sun, and then by Oracle, […]Read more
We all enjoyed Yoshinori announcement of HandlerSocket, the plugin to MySQL which open NOSQL way to access data stored in InnoDB.
The published results are impressive, but I want to understand some, that’s why I run couple more experiments.
In blog post Yoshinori used the case when all data fits into memory, and one of question […]
There’s an interview with Baron Schwartz (that’s me) on WebPulp.tv. Topics include the history of Percona’s software such as Percona Server (our version of the MySQL database server) and XtraBackup, what we do at Percona, what tools we use to do it, how to think logically about performance optimization, what ugly surprises happen […]Read more