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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

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

MySQL Indexing Best Practices: Webinar Questions Followup

August 16, 2012 By Peter Zaitsev 4 Comments

I had a lot of questions on my MySQL Indexing: Best Practices Webinar (both recording and slides are available now) We had lots of questions. I did not have time to answer some and others are better answered in writing anyway. Q: One developer on our team wants to replace longish (25-30) indexed varchars with [...]

Filed Under: Insight for DBAs, MySQL

Percona XtraBackup 1.6

April 12, 2011 By Fred Linhoss 15 Comments

Percona XtraBackup 1.6 is now available for download and is the current stable release version of XtraBackup.

Filed Under: MySQL, Percona Software

Optimizing slow web pages with mk-query-digest

April 7, 2011 By Aurimas Mikalauskas 14 Comments

I don’t use many tools in my consulting practice but for the ones I do, I try to know them as best as I can. I’ve been using mk-query-digest for almost as long as it exists but it continues to surprise me in ways I couldn’t imagine it would. This time I’d like to share [...]

Filed Under: Insight for DBAs, MySQL Tagged With: Ideas, MySQL, Percona Server, Tips, Tools

High availability for MySQL on Amazon EC2 â€“ Part 2 – Setting up the initial instances

June 29, 2010 By Yves Trudeau 9 Comments

This post is the second of a series that started here. The first step to build the HA solution is to create two working instances, configure them to be EBS based and create a security group for them. A third instance, the client, will be discussed in part 7. Since this will be a proof [...]

Filed Under: Insight for DBAs, MySQL Tagged With: High Availability

XtraDB storage engine release 1.0.2-3 (Spring edition) codename Sapporo

March 2, 2009 By Evgeniy Stepchenko 10 Comments

Today we announce release 1.0.2-3 of our XtraDB storage engine. Here is a list of enhancements: Move to MySQL 5.1.31 Scalability fix â€” ability to use several rollback segments Increasing the number of rseg may be helpful for CPU scale of write-intentional workloads. See benchmark results. Scalability fix â€” replaced page_hash mutex to page_hash read-write [...]

Filed Under: Percona Software Tagged With: Percona, Release, XtraDB, XtraDB InnoDB scalability

Idea: Couple of more string types

April 18, 2008 By Peter Zaitsev 12 Comments

MySQL has a lot of string data types – CHAR, VARCHAR, BLOB, TEXT, ENUM and bunch of variants such as VARBINARY but I think it is not enough I would also like to see type HEXCHAR which would be able to store hex strings, such as those returned as MD5() and SHA1() efficiently. With little [...]

Filed Under: Insight for Developers Tagged With: Ideas

Benchmarking Percona Server TokuDB vs InnoDB

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) ?

MySQL Indexing Best Practices: Webinar Questions Followup

Percona XtraBackup 1.6

Optimizing slow web pages with mk-query-digest

High availability for MySQL on Amazon EC2 â€“ Part 2 – Setting up the initial instances

XtraDB storage engine release 1.0.2-3 (Spring edition) codename Sapporo

Idea: Couple of more string types

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