An attendee to Espen’s recent webinar asked how to check tables for corruption. This kind of ties into my recent post on InnoDB’s handling of corrupted pages, because the best way to check for corruption is with CHECK TABLES, but if a page is corrupt, InnoDB will crash the server to prevent access to the [...]
Bug#12704861
As Mark pointed out, there isn’t a lot of detail in the release notes about what could potentially be a very serious problem that is fixed in MySQL 5.1.60. I’ll repeat here the full documentation from the release notes: “InnoDB Storage Engine: Data from BLOB columns could be lost if the server crashed at a precise [...]
Connecting orphaned .ibd files
There are two ways InnoDB can organize tablespaces. First is when all data, indexes and system buffers are stored in a single tablespace. This is typicaly one or several ibdata files. A well known innodb_file_per_table option brings the second one. Tables and system areas are split into different files. Usually system tablespace is located in [...]
Percona at WebConf Riga 2010
My colleague Aleksandr Kuzminsky will be speaking at WebConf Riga 2010 next month on XtraBackup: Hot Backups and More and Recovery of Lost or Corrupted InnoDB Tables. WebConf is the first big conference of its kind in the Baltic states (Estonia, Latvia, Lithuania) and we are very happy to be participating. In addition to Aleksandr’s [...]
Percona talks at OpenSQL Camp this weekend
Four Perconians (perconites?) will be at OpenSQL Camp in Sankt Augustin, Germany this weekend presenting talks on: Recovery of Lost or Corrupted InnoDB Tables Keep your MySQL backend online no matter what XtraDB — InnoDB on steroids Xtrabackup for MySQL If you would like to stop by and say hello, we are Aleksandr, Istvan, Morgan [...]
Why you can’t rely on a replica for disaster recovery
A couple of weeks ago one of my colleagues and I worked on a data corruption case that reminded me that sometimes people make unsafe assumptions without knowing it. This one involved SAN snapshotting that was unsafe. In a nutshell, the client used SAN block-level replication to maintain a standby/failover MySQL system, and there was [...]
Recover BLOB fields
For a long time long types like BLOB, TEXT were not supported by Percona InnoDB Recovery Tool. The reason consists in a special way InnoDB stores BLOBs. An InnoDB table is stored in a clustered index called PRIMARY. It must exist even if a user hasn’t defined the primary index. The PRIMARY index pages are [...]
Presentations Announcement: 2010 O’Reilly MySQL Conference & Expo
The Percona team participated at this year’s O’Reilly MySQL Conference & Expo held April 12-15, 2010 in Santa Clara, California. We gave a lot of talks on…
Author: Peter Zaitsev, Justin Swanhart
MySQL Graphing and Trending with Cacti
Author: Baron Schwartz
Percona‘s Performance and Feature Enhancements to MySQL and InnoDB
Author: Bill Schuler, Baron Schwartz…a Bottleneck
Author: Morgan Tocker
XtraBackup Hot Backups and More
Author: Vadim Tkachenko, Morgan Tocker
You can also read more about this conference on Percona site.
Percona sessions at the MySQL conference
Many Percona employees will be at the 2010 MySQL conference. We’ll be giving a lot of informative technical talks on various topics. Here’s a list: Morgan Tocker, Baron Schwartz: Diagnosing and Fixing MySQL Performance Problems Peter Zaitsev: Scaling Applications with Caching, Sharding and Replication Baron Schwartz: EXPLAIN Demystified Vadim Tkachenko: An Overview of Flash Storage [...]
Recovery beyond data restore
Quite frequently I see customers looking at recovery as on ability to restore data from backup which can be far from being enough to restore the whole system to operating state, especially for complex systems. Instead of looking just at data restore process you better look at the whole process which is required to bring [...]

