October 20, 2014

MySQL Audit Plugin now available in Percona Server 5.5 and 5.6

The new Percona Server 5.5.37-35.0 and Percona Server 5.6.17-65.0-56, announced yesterday (May 6), both include the open source version of the MySQL Audit Plugin. The MySQL Audit Plugin is used to log all queries or connections (“audit” MySQL usage). Until yesterday’s release, the MySQL Audit Plugin was only available in MySQL Enterprise. EDIT:  Just to be clear, this implementation […]

trx descriptors: MySQL performance improvements in Percona Server 5.5.30-30.2

One major problem in terms of MySQL performance that still stands in the way of InnoDB scalability is the trx_list scan on consistent read view creation. It was originally reported as a part of MySQL bug #49169 and can be described as follows. Whenever a connection wants to create a consistent read, it has to […]

Is MySQL 5.6 slower than MySQL 5.5?

There have been a number reports/benchmarks showing MySQL 5.6 to be slower than MySQL 5.5 on variety of workloads. There are many possible reasons and I believe we will learn about many of them in the next few weeks and months as MySQL 5.6 is starting to get production battle-tested and there is inflow of […]

Review of MySQL 5.6 Defaults Changes

James Day just posted the great summary of defaults changes in MySQL 5.6 compared to MySQL 5.5 In general there are a lot of good changes and many defaults are now computed instead of hardcoded. Though some of changes are rather puzzling for me. Lets go over them: back_log = 50 + ( max_connections / […]

DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL

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 […]

When would you use SAN with MySQL ?

One question which comes up very often is when one should use SAN with MySQL, which is especially popular among people got used to Oracle or other Enterprise database systems which are quite commonly deployed on SAN. My question in such case is always what exactly are you trying to get by using SAN ?

MySQL and PostgreSQL SpecJAppServer benchmark results

Listening to Josh Berkus presentation on OSCON today I decided to take a closer look at SpecJAppServer benchmarks results which were published by PostgreSQL recently and which as Josh Puts it “This publication shows that a properly tuned PostgreSQL is not only as fast or faster than MySQL, but almost as fast as Oracle (since […]

Watch out for Marketing benchmarks

Whenever I see benchmark results I try to understand if it is technical benchmark – made by people seeking the truth or it is done by Marketing department to wash your brains. Watch out. Whenever you treat marketing benchmarks as technical ones, you make make wrong decision. Take a look at MySQL 5.0 Benchmarks Whitepaper […]

SysBench – benchmark tool

Sysbench is benchmark developed by Alexey Kopytov (software engineer @ MySQL AB) – http://sysbench.sourceforge.net/ and I want to write a short intro about this tool as sysbench is one of software for my everyday use. For example, SUN published their Solaris vs RedHat stuff based on sysbench’s results (Peter and me provided performance consutling for […]

How to improve InnoDB performance by 55% for write-bound loads

During April’s Percona Live MySQL Conference and Expo 2014, I attended a talk on MySQL 5.7 performance an scalability given by Dimitri Kravtchuk, the Oracle MySQL benchmark specialist. He mentioned at some point that the InnoDB double write buffer was a real performance killer. For the ones that don’t know what the innodb double write […]