May 18, 2013

MySQL Workshops: Chicago & London this April

Percona will be in Chicago and London the week of April 8th delivering two 2-day MySQL workshops. For our MPB readers, we are offering a 15% discount. Just use MPB15A when purchasing your tickets to one or both MySQL workshops. Scaling and Optimization for MySQL on Monday & Tuesday, April 8 & 9 This MySQL workshop [...]

MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark

So far most of the benchmarks posted about MySQL 5.6 use the sysbench OLTP workload.  I wanted to test a set of queries which, unlike sysbench, utilize joins.  I also wanted an easily reproducible set of data which is more rich than the simple sysbench table.  The Star Schema Benchmark (SSB) seems ideal for this. [...]

InnoDB Full-text Search in MySQL 5.6 (part 1)

I’ve never been a very big fan of MyISAM; I would argue that in most situations, any possible advantages to using MyISAM are far outweighed by the potential disadvantages and the strengths of InnoDB. However, up until MySQL 5.6, MyISAM was the only storage engine with support for full-text search (FTS). And I’ve encountered many [...]

Measuring the amount of writes in InnoDB redo logs

Choosing a good InnoDB log file size is key to InnoDB write performance. This can be done by measuring the amount of writes in the redo logs. You can find a detailed explanation in this post. To sum up, here are the main points: The redo logs should be large enough to store at most [...]

Troubleshooting MySQL Memory Usage

One of the most painful troubleshooting tasks with MySQL is troubleshooting memory usage. The problem usually starts like this – you have configured MySQL to use reasonable global buffers, such as innodb_buffer_size, key_buffer_size etc, you have reasonable amount of connections but yet MySQL takes much more memory than you would expect, causing swapping or other [...]

Percona Server 5.1.58-12.9

Percona is glad to announce the release of Percona Server 5.1.58-12.9 on August 12, 2011 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.1.58, including all the bug fixes in it, Percona Server 5.1.58-12.9 is now the current stable release in the 5.1 series. All of Percona’s software is open-source and free, all [...]

Why you should ignore MySQL’s key cache hit ratio

I have not caused a fist fight in a while, so it’s time to take off the gloves. I claim that somewhere around of 99% of advice about tuning MySQL’s key cache hit ratio is wrong, even when you hear it from experts. There are two major problems with the key buffer hit ratio, and [...]

Copying InnoDB tables between servers

The feature I announced some time ago http://www.mysqlperformanceblog.com/2009/06/08/impossible-possible-moving-innodb-tables-between-servers/ is now available in our latest releases of XtraBackup 0.8.1 and XtraDB-6. Now I am going to show how to use it (the video will be also available on percona.tv). Let’s take tpcc schema and running standard MySQL ® 5.0.83, and assume we want to copy order_line [...]

How much memory can MySQL use in the worst case?

I vaguely recall a couple of blog posts recently asking something like “what’s the formula to compute mysqld’s worst-case maximum memory usage?” Various formulas are in wide use, but none of them is fully correct. Here’s why: you can’t write an equation for it.

Using Multiple Key Caches for MyISAM Scalability

I have written before – MyISAM Does Not Scale, or it does quite well – two main things stopping you is table locks and global mutex on the KeyCache. Table Locks are not the issue for Read Only workload and write intensive workloads can be dealt with by using with many tables but Key Cache [...]