Search Results for: mysql flush slow query log

MySQL: Followup on UNION for query optimization, Query profiling

Few days ago I wrote an article about using UNION to implement loose index scan. First I should mention double IN also works same way so you do not have to use the union. So changing query to:

So as you see there are really different types of ranges in MySQL. IN range allows […]

MySQL Crash Recovery

MySQL is known for its stability but as any other application it has bugs so it may crash sometime. Also operation system may be flawed, hardware has problems or simply power can go down which all mean similar things – MySQL Shutdown is unexpected and there could be various inconsistences. And this is not only […]

Galera replication – how to recover a PXC cluster

Galera replication for MySQL brings not only the new, great features to our ecosystem, but also introduces completely new maintenance techniques. Are you concerned about adding such new complexity to your MySQL environment? Perhaps that concern is unnecessarily. I am going to present here some simple tips that hopefully will let fresh Galera users prevent […]

Do not trust vmstat IOwait numbers

I’ve been running a benchmark today on my old test box with conventional hard drives (no raid with BBU) and noticed something unusual in the CPU utilization statistics being reported. The benchmark was run like this:

Which means: create 64 threads and hammer the database with queries as quickly as possible. As the test […]

Percona Server 5.6.17-65.0 is now available

Percona is glad to announce the release of Percona Server 5.6.17-65.0 on May 6th, 2014. Downloads are available here and from the Percona Software Repositories. Based on MySQL 5.6.17, including all the bug fixes in it, Percona Server 5.6.17-65.0 is the current GA release in the Percona Server 5.6 series. All of Percona’s software is […]

Percona Server 5.5.37-35.0 is now available

Percona is glad to announce the release of Percona Server 5.5.37-35.0 on May 6th, 2014 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.37, including all the bug fixes in it, Percona Server 5.5.37-35.0 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of the release […]