Emergency

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 …

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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 …

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Advanced index analysis with mk-index-usage

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, …

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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 …

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Implementing Parallel Replication in MySQL

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 …

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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, …

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An argument for not using mysqldump

I have a 5G mysqldump which takes 30 minutes to restore from backup.  That means that when the database reaches 50G, it should take 30×10=5 hours to restore.  Right?  Wrong.

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Percona’s Commitments to MySQL Users

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 …

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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 …

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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, …

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