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Benchmarking Percona Server TokuDB vs InnoDB

May 7, 2013 By Vadim Tkachenko 32 Comments

After compiling Percona Server with TokuDB, of course I wanted to compare InnoDB performance vs TokuDB. I have a particular workload I’m interested in testing – it is an insert-intensive workload (which is TokuDB’s strong suit) with some roll-up aggregation, which should produce updates in-place (I will use INSERT .. ON DUPLICATE KEY UPDATE statements [...]

Filed Under: Benchmarks, MySQL, Percona Server Tagged With: Benchmarking, InnoDB, Percona Server, TokuDB

Is your MySQL buffer pool warm? Make it sweat!

April 16, 2013 By Peter Boros 6 Comments

Today’s blog post diving into the waters of the MySQL buffer pool is a cross-post from Groupon’s engineering blog, and is Part 1 of 2. Thank you to Kyle Oppenheim at Groupon for contributing to this project and post. We’ll be posting Part 2 on Thursday. I’ll be at the Percona Live MySQL Conference and [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL, Percona Software Tagged With: Groupon, Kyle Oppenheim, MySQL buffer pool, MySQL High Availability, Percona Playback, Peter Boros, Replaying Queries, Warm standby server

InnoDB Full-text Search in MySQL 5.6: Part 2, The Queries!

March 4, 2013 By Ernie Souhrada 7 Comments

This is part 2 in a 3 part series. In part 1, we took a quick look at some initial configuration of InnoDB full-text search and discovered a little bit of quirky behavior; here, we are going to run some queries and compare the result sets. Our hope is that the one of two things [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: Ernie Souhrada, FTS, FullText Search, InnoDB, MyISAM, MySQL 5.6

Percona XtraDB Cluster (PXC): what about GRA_*.log files ?

December 19, 2012 By Frederic Descamps Leave a Comment

How easy is it to identify and debug Percona XtraDB Cluster replication problem ? If you are using PXC, you may have already seen in your datadirectory several log files starting with GRA_ Those files correspond to a replication failure. That means the slave thread was not able to apply one transaction. For each of [...]

Filed Under: MySQL, Percona Software, XtraDB Cluster

When is MIN(DATE) != MIN(DATE) ?

September 4, 2012 By Ernie Souhrada 5 Comments

Inspiration for this post is courtesy of a friend and former colleague of mine, Greg Youngblood, who pinged me last week with an interesting MySQL puzzle. He was running Percona Server 5.5.21 with a table structure that looks something like this:

CREATE TABLE foo (
 id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
 uid INT UNSIGNED NOT NULL,
 update_time DATETIME NOT NULL,
 ....
 INDEX `uid` (uid, update_time),
 INDEX `bar` (some_other_columns)
 ....
) ENGINE=InnoDB;

CREATE TABLE foo (

id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,

uid INT UNSIGNED NOT NULL,

update_time DATETIME NOT NULL,

....

INDEX `uid` (uid, update_time),

INDEX `bar` (some_other_columns)

....

) ENGINE=InnoDB;

When he ran this query:

SELECT MIN(update_time) FROM foo WHERE update_time IS NOT NULL AND update_time <> '0000-00-00 00:00:00';

1	SELECT MIN(update_time) FROM foo WHERE update_time IS NOT NULL AND update_time <> '0000-00-00 00:00:00';

The result came back as 2012-06-22 10:28:16. [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL

Percona Server 5.1.58-12.9

August 17, 2011 By Stewart Smith 2 Comments

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 [...]

Filed Under: MySQL, Percona Software

Using any general purpose computer as a special purpose SIMD computer

May 16, 2011 By Justin Swanhart 5 Comments

Often times, from a computing perspective, one must run a function on a large amount of input. Often times, the same function must be run on many pieces of input, and this is a very expensive process unless the work can be done in parallel. Shard-Query introduces set based processing, which on the surface appears [...]

Filed Under: MySQL

Distributed Set Processing with Shard-Query

May 14, 2011 By Justin Swanhart 27 Comments

Can Shard-Query scale to 20 nodes? Peter asked this question in comments to to my previous Shard-Query benchmark. Actually he asked if it could scale to 50, but testing 20 was all I could due to to EC2 and time limits. I think the results at 20 nodes are very useful to understand the performance: [...]

Filed Under: MySQL

Shard-Query EC2 images available

May 11, 2011 By Justin Swanhart 2 Comments

Infobright and InnoDB AMI images are now available There are now demonstration AMI images for Shard-Query. Each image comes pre-loaded with the data used in the previous Shard-Query blog post. The data in the each image is split into 20 “shards”. This blog post will refer to an EC2 instances as a node from here [...]

Filed Under: MySQL

Tuning InnoDB Concurrency Tickets

May 24, 2010 By Ryan Lowe 5 Comments

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 [...]

Filed Under: Benchmarks, Insight for DBAs, MySQL Tagged With: Concurrency Tickets, InnoDB, InnoDB Concurrency, innodb_concurrency_tickets, Tuning

Benchmarking Percona Server TokuDB vs InnoDB

Is your MySQL buffer pool warm? Make it sweat!

InnoDB Full-text Search in MySQL 5.6: Part 2, The Queries!

Percona XtraDB Cluster (PXC): what about GRA_*.log files ?

When is MIN(DATE) != MIN(DATE) ?

Percona Server 5.1.58-12.9

Using any general purpose computer as a special purpose SIMD computer

Distributed Set Processing with Shard-Query

Shard-Query EC2 images available

Tuning InnoDB Concurrency Tickets

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