Monthly Archives - November 2010

The perils of uniform hardware and RAID auto-learn cycles

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

Shard-Query adds parallelism to queries

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 […]

Read more

Lost innodb tables, xfs and binary grep

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

Webinar: MyISAM to InnoDB migration

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 […]

Read more

HandlerSocket on SSD

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 […]

Read more

Baron Schwartz interviewed on WebPulp.tv

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