August 29, 2014

Ultimate MySQL variable and status reference list

I am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to look up blog posts on variables, or look for content in the Percona documentation or forums. So I present to you what is now my newest Firefox toolbar bookmark: an option and […]

MySQL Query Cache WhiteSpace and comments

Commenting on my previous post on MySQL Query Cache Gerry pokes me as I’m all wrong and both comments and whitespace are fixed in MySQL 5.0. This was not what I remember seeing in production so I decided to do some tests on the matter:

Innodb Undelete and Sphinx Support

At Percona we are pleased to announce couple of services which should be helpful to MySQL Community and which are not offered by MySQL, Oracle and other companies I know about. First we now do Data Recovery for MySQL. We’re mainly focused on Innodb with this one because it has distinct page structure which allows […]

MySQL Query Cache

MySQL has a great feature called “Query Cache” which is quite helpful for MySQL Performance optimization tasks but there are number of things you need to know. First let me clarify what MySQL Query Cache is – I’ve seen number of people being confused, thinking MySQL Query Cache is the same as Oracle Query Cache […]

When (and how) to move an InnoDB table outside the shared tablespace

In my last post, “A closer look at the MySQL ibdata1 disk space issue and big tables,” I looked at the growing ibdata1 problem under the perspective of having big tables residing inside the so-called shared tablespace. In the particular case that motivated that post, we had a customer running out of disk space in his […]

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 […]

Innodb redo log archiving

Percona Server 5.6.11-60.3 introduces a new “log archiving” feature. Percona XtraBackup 2.1.5 supports “apply archived logs.” What does it mean and how it can be used? Percona products propose three kinds of incremental backups. The first is full scan of data files and comparison the data with backup data to find some delta. This approach […]

Introducing backup locks in Percona Server

TL;DR version: The backup locks feature introduced in Percona Server 5.6.16-64.0 is a lightweight alternative to FLUSH TABLES WITH READ LOCK and can be used to take both physical and logical backups with less downtime on busy servers. To employ the feature with mysqldump, use mysqldump –lock-for-backup –single-transaction. The next release of Percona XtraBackup will […]

Percona Toolkit 2.1.11 is now available

Percona is glad to announce the release of Percona Toolkit 2.1.11 on March 4th, 2013 (Downloads are available here). Bugs Fixed: Fixed bug 1279502: –version-check behaves like spyware The configuration for what information Percona Toolkit should retrieve is not hard-coded in the scripts. Instead, it is downloaded from v.percona.com. One of the possible parameters was the name […]

The ARCHIVE Storage Engine – does it do what you expect?

Sometimes there is a need for keeping large amounts of old, rarely used data without investing too much on expensive storage. Very often such data doesn’t need to be updated anymore, or the intent is to leave it untouched. I sometimes wonder what I should really suggest to our Support customers. For this purpose, the […]