September 22, 2014

Percona Server: Improve Scalability with Percona Thread Pool

By default, for every client connection the MySQL server spawns a separate thread which will process all statements for this connection. This is the ‘one-thread-per-connection’ model. It’s simple and efficient until some number of connections N is reached. After this point performance of the MySQL server will degrade, mostly due to various contentions caused by […]

MySQL and the SSB – Part 2 – MyISAM vs InnoDB low concurrency

This blog post is part two in what is now a continuing series on the Star Schema Benchmark. In my previous blog post I compared MySQL 5.5.30 to MySQL 5.6.10, both with default settings using only the InnoDB storage engine.  In my testing I discovered that innodb_old_blocks_time had an effect on performance of the benchmark.  There was […]

thread_concurrency doesn’t do what you expect

Over the last months I’ve seen lots of customers trying to tune the thread concurrency inside MySQL with the variable thread_concurrency. Our advice is: stop wasting your time, it does nothing on GNU/Linux Some of the biggest GNU/Linux distributions includes the variable thread_concurrency in their my.cnf file by default. One example is Debian and its […]

Tuning InnoDB Concurrency Tickets

InnoDB has an oft-unused parameter innodb_concurrency_tickets that seems widely misunderstood. From the docs: “The number of threads that can enter InnoDB concurrently is determined by the innodb_thread_concurrency variable. A thread is placed in a queue when it tries to enter InnoDB if the number of threads has already reached the concurrency limit. When a thread […]

Percona Server 5.6.15-63.0 is now available

Percona is glad to announce the release of Percona Server 5.6.15-63.0 on December 19th, 2013 (Downloads are available here and from the Percona Software Repositories. Based on MySQL 5.6.15, including all the bug fixes in it, Percona Server 5.6.15-63.0 is the current GA release in the Percona Server 5.6 series. All of Percona’s software is […]

Crash-resistant replication: How to avoid MySQL replication errors

Percona Server’s “crash-resistant replication” feature is useful in versions 5.1 through 5.5. However, in Percona Server 5.6 it’s replaced with Oracle MySQL 5.6’s “crash safe replication” feature, which has it’s own implementation (you can read more about it here). A MySQL slave normally stores its position in files master.info and relay-log.info which are updated by […]

Percona XtraDB Cluster 5.5.30-23.7.4 for MySQL now available

Percona is glad to announce the release of Percona XtraDB Cluster 5.5.30-23.7.4 for MySQL on April 17, 2013. Binaries are available from the downloads area or from our software repositories. New Features: Percona XtraDB Cluster has implemented initial implementation of weighted quorum. Weight for node can be assigned via pc.weight option in the wsrep_provider_options variable. […]

New SpecJAppServer results at MySQL and Sun.

As you likely have seen Sun has posted the new SpecJAppServer Results More information from Tom Daly can be found here These results are quite interesting for me as I worked on some of the previous SpecJAppServer Benchmarks several years ago while being employed by MySQL. These are great results, plus they can be relevant […]

Heikki Tuuri answers to Innodb questions, Part II

I now got answers to the second portions of the questions you asked Heikki. If you have not seen the first part it can be found here. Same as during last time I will provide my comments for some of the answers under PZ and will use HT for original Heikkis answer. Q26: You also […]

Innodb usability and ease of use.

It always surprised me how little Innodb team seems to think about product usability/ease of use, when it comes to settings, performance management etc. I could understand many things 5 years ago, like a lot of information being available only in hard to parse SHOW INNODB STATUS output or even uglier hacks with creating tables […]