Percona is glad to announce the release of Percona Server 5.5.23-25.3 on May 16, 2012 (Downloads are available here and from the Percona Software Repositories ). Based on MySQL 5.5.23 , including all the bug fixes in it, Percona Server...
In MySQL Cluster there is a limiting factor in the receive threads that limits our update performance to about 0.5M update transactions per node group per second (usually 2 nodes per node group). In MySQL Cluster 7.2.7 we have removed most of...
InnoDB locks the buffer pool mutex and scans the LRU to remove pages when DROP TABLE is done for a table that uses innodb_file_per_table . If you read the source you might notice that it scans the LRU twice, once...
The explain statement can be an important tool for understanding how a query is being executed and what you can do to make it run better. Although the output of EXPLAIN is relatively straightforward it can be confusing to inexperienced users or...
Users of MySQL Replication sometimes throttle client requests to give slaves time to catch up to the master. PECL/mysqlnd_ms 1.4, the current development version, features some throttling through the quality-of-service filter and global...
I have always found it strange that we do not have a MySQL user group in Sweden - this is the country where the MySQL saga started. Therefore I am delighted to announce that since today we have a user group in Sweden and I hope it will be a...
Often I see a SQL problem solved incorrectly and I do not mean inefficiently. Simply incorrectly. In many cases the developer remains unaware that they aren t getting the results they were expecting or even if a result is correct, it is only by...
In my previous post, http://database-scalability.blogspot.com/2012/05/oltp-vs-analytics.html , I reviewed the differences between OLTP and Analytics databases. Scale challenges are different between...
Have you ever tried to kill a query, but rather than just go away, it remained among the running ones for an extended period of time? Or perhaps you have noticed some threads makred with killed showing up from time to time and not actually dying....
My old post ( http://www.jroller.com/mmatthews/entry/speeding_up_batch_inserts_for ) on the performance gains from batch rewritten statements gets regurgitated in various forums, and conference sessions, and often people miss the nuances of it....