Recently, I found myself involved in the migration of a large read-only InnoDB database to MyISAM (eventually packed). The only issue was that for one of the table, we were talking of 5 TB of data, 23B rows. Not small… I calculated that with something like insert into MyISAM_table… select * from Innodb_table… would take [...]
Replaying database load with Percona Playback
October 25, 2012 By 9 Comments
If you are planning to upgrade or make any configuration change on your MySQL database the first advice usually is: – Benchmark! How should we do that benchmark? People usually run generic benchmark tools like sysbench, tpcc or mysqlslap that are good to know the number of transactions per seconds that a database can do [...]
Announcing Percona XtraBackup 2.0.3
October 1, 2012 By 1 Comment
Percona is glad to announce the release of Percona XtraBackup 2.0.3 on October 1st, 2012. Downloads are available from our download site here and Percona Software Repositories. This release is the current GA (Generally Available) stable release in the 2.0 series. New Features: innobackupex now supports new –move-back option that can be used instead of –copy-back in case [...]
MySQL Indexing Best Practices: Webinar Questions Followup
August 16, 2012 By 4 Comments
I had a lot of questions on my MySQL Indexing: Best Practices Webinar (both recording and slides are available now) We had lots of questions. I did not have time to answer some and others are better answered in writing anyway. Q: One developer on our team wants to replace longish (25-30) indexed varchars with [...]
Percona Server 5.5.25-27.0 release delayed
June 28, 2012 By 2 Comments
Due to a bug in upstream MySQL ( http://bugs.mysql.com/bug.php?id=65745 ), we’ve decided to delay the release of the next Percona Server release until it is resolved. We had originally expected to release Percona Server 5.5.25-27.0 today and instead I’m informing you that we are not. Quoting Hartmut, who reported the bug: An UPDATE that should only modify [...]
DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL
June 22, 2012 By 33 Comments
Suppose you have turned on innodb_file_per_table (which means that each table has its own tablespace), and you have to drop tables in a background every hour or every day. If its once every day then you can probably schedule the table dropping process to run during off-peak hours. But I have seen cases where the [...]
Find and remove duplicate indexes
June 20, 2012 By 9 Comments
Having duplicate keys in our schemas can hurt the performance of our database: They make the optimizer phase slower because MySQL needs to examine more query plans. The storage engine needs to maintain, calculate and update more index statistics DML and even read queries can be slower because MySQL needs update fetch more data to [...]
A case for MariaDB’s Hash Joins
May 31, 2012 By Leave a Comment
MariaDB 5.3/5.5 has introduced a new join type “Hash Joins” which is an implementation of a Classic Block-based Hash Join Algorithm. In this post we will see what the Hash Join is, how it works and for what types of queries would it be the right choice. I will show the results of executing benchmarks [...]
Announcement of Percona XtraDB Cluster 5.5.23
May 14, 2012 By 16 Comments
Our previous GA release of Percona XtraDB Cluster caused a lot of interest and feedback. I am happy to announce next version Percona XtraDB Cluster 5.5.23, which comes with bug fixes and improvements. List of changes: Fixes merged from upstream (Codership-mysql) Support for MyISAM, now changes to MyISAM tables are replicated to other nodes Improvements [...]
Testing Intel SSD 520
May 1, 2012 By 8 Comments
Following my previous benchmarks of SATA SSD cards I got Intel SSD 520 240GB into my hands. In this post I show the results of raw IO performance of this card.
