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Benchmarking Percona Server TokuDB vs InnoDB

May 7, 2013 By Vadim Tkachenko 29 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

Percona Server 5.5.30-30.2 rerelease fixes non-restart issue

April 24, 2013 By Ignacio Nin Leave a Comment

In our last 5.5 series release of Percona Server, we included a regression in the RPM packaging that prevented the server from restarting following an upgrade — instead, the server would remain stopped after the upgrade was completed regardless of its state before updating. This caused some problems for some users, especially if automatic upgrading was configured [...]

Filed Under: MySQL, Percona Software

MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark

March 11, 2013 By Justin Swanhart 7 Comments

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. [...]

Filed Under: MySQL Tagged With: InnoDB plugin, Justin Swanhart, MySQL 5.5, MySQL 5.6, Star Schema Benchmark (SSB), sysbench

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

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

February 26, 2013 By Ernie Souhrada 1 Comment

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 [...]

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

Implications of Metadata Locking Changes in MySQL 5.5

February 1, 2013 By Ovais Tariq 9 Comments

While most of the talk recently has mostly been around the new changes in MySQL 5.6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the Metadata Locking related changes that were introduced in MySQL 5.5.3. It appears that the implications of Metadata Locking have not [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: alter table, ddl, metadata locking, query cache, table cache, transaction, Transaction isolation

Read/Write Splitting with PHP Webinar Questions Followup

January 23, 2013 By Bill Karwin 4 Comments

Today I gave a presentation on “Read/Write Splitting with PHP” for Percona Webinars. If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions. I answered as many as I could during the session, but here are [...]

Filed Under: Events and Announcements, Insight for Developers, MySQL Tagged With: MySQL, php, Replication

Recovery after DROP & CREATE

August 22, 2012 By Aleksandr Kuzminsky 1 Comment

In a very popular data loss scenario a table is dropped and empty one is created with the same name. This is because mysqldump in many cases generates the “DROP TABLE” instruction before the “CREATE TABLE”:

DROP TABLE IF EXISTS `actor`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `actor` (
  `actor_id` smallint(5) unsigned NOT NULL AUTO_INCREMENT,
  `first_name` varchar(45) NOT NULL,
  `last_name` varchar(45) NOT NULL,
  `last_update` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`actor_id`),
  KEY `idx_actor_last_name` (`last_name`)
) ENGINE=InnoDB AUTO_INCREMENT=201 DEFAULT CHARSET=utf8;
/*!40101 SET character_set_client = @saved_cs_client */;

DROP TABLE IF EXISTS `actor`;

/*!40101 SET @saved_cs_client = @@character_set_client */;

/*!40101 SET character_set_client = utf8 */;

CREATE TABLE `actor` (

`actor_id` smallint(5) unsigned NOT NULL AUTO_INCREMENT,

`first_name` varchar(45) NOT NULL,

`last_name` varchar(45) NOT NULL,

`last_update` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,

PRIMARY KEY (`actor_id`),

KEY `idx_actor_last_name` (`last_name`)

) ENGINE=InnoDB AUTO_INCREMENT=201 DEFAULT CHARSET=utf8;

/*!40101 SET character_set_client = @saved_cs_client */;

If there were no subsequent CREATE TABLE the recovery would be trivial. Index_id of the PRIMARY index of [...]

Filed Under: MySQL Tagged With: drop table, InnoDB, Recovery

Percona XtraDB Cluster: Failure Scenarios with only 2 nodes

July 25, 2012 By Frederic Descamps 6 Comments

During the design period of a new cluster, it is always advised to have at least 3 nodes (this is the case with PXC but it’s also the same with PRM). But why and what are the risks ? The goal of having more than 2 nodes, in fact an odd number is recommended in [...]

Filed Under: MySQL, XtraDB Cluster

On Character Sets and Disappearing Tables

June 21, 2012 By Ernie Souhrada 1 Comment

The MySQL manual tells us that regardless of whether or not we use “SET FOREIGN_KEY_CHECKS=0″ before making schema changes, InnoDB will not allow a column referenced by a foreign key constraint to be modified in such a way that the foreign key will reference a column with a mismatched data type. For instance, if we [...]

Filed Under: Insight for DBAs, MySQL

Benchmarking Percona Server TokuDB vs InnoDB

Percona Server 5.5.30-30.2 rerelease fixes non-restart issue

MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark

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

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

Implications of Metadata Locking Changes in MySQL 5.5

Read/Write Splitting with PHP Webinar Questions Followup

Recovery after DROP & CREATE

Percona XtraDB Cluster: Failure Scenarios with only 2 nodes

On Character Sets and Disappearing Tables

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