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Displaying posts with tag: MySQL 5.5 (reset)
Hotbackup of Galera Cluster for MySQL using Xtrabackup


Hot backups are important for high availability, they can run without blocking the application. Percona Xtrabackup is a great tool for backing up InnoDB data. 
We have created a backup tool called s9s_backup that makes Xtrabackup really easy to use, and is fully integrated with ClusterControl, which means that you can schedule backups with ease and view the backups that you have taken, and also restore the backups with no pain.


s9s_backup is available in the lastest version of ClusterControl or you can download it here.



Is mysqldump totally useless then?

No. If you would like to isolate and load only one table, mysqldump is great, or if you want to …

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When EXPLAIN estimates can go wrong!

This is the title of my first blog post on MySQL Performance Blog. It deals with a customer case where the customer was facing a peculiar problem where the rows column in the EXPLAIN output of the query was totally off. The actual number of rows was 18 times more than the number of rows reported by MySQL in the output of EXPLAIN. Now this can be a real pain as MySQL uses “the number of rows” estimation to pick and choose indexes and it could really be picking up a wrong index simply because of the wrong estimate. You...

The post When EXPLAIN estimates can go wrong! appeared first on ovais.tariq.

Multi-master and read slaves using Severalnines

This blog post shows how you can use the Severalnines Configurator for MySQL Replication to deploy a Multi-master replication setup, and install ClusterControl.
You can also watch videos showing what is described below or read an even more detailed tutorial.

When the deployment is finished you have a set of tools to manage and monitor replication, as well as to add new slaves, and to perform failover.
You can choose:

  • The number of slaves you wish to connect to the …
[Read more]
Re-implementing udf_init_error in MySQL 5.5 and up

To whom it may concern -

Today, I received an email from a user of the udf_init_error UDF (which resides in the lib_mysqludf_udf library). The purpose of this UDF is to generate an error condition, which can be used to abruptly terminate a trigger or stored procedure. As such it is a workaround for bug #11661. This is all described extensively in my now ancient article here.

The user wrote me because of a problem experienced in MySQL 5.5: ...calling

select …
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What a difference Atomics can make

Following up to my previous blog on graphing statement execution in performance_schema, Sunny Bains on the InnoDB team pointed out that in looking at the INSERT graph, he didn’t think I had atomic operations enabled within my build.

Particularly here (from trunk):

225 /******************************************************************//**
226 Increments lock_word the specified amount and returns new value.
227 @return lock->lock_word after increment */
228 UNIV_INLINE
229 lint
230 rw_lock_lock_word_incr(
231 /*===================*/
232         rw_lock_t*      lock,           /*!< in/out: rw-lock */
233         ulint           amount)         /*!< in: amount of increment */
234 {
235 #ifdef …
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Setting up Multi-master and read slaves using Severalnines




Read the detailed replication tutorial instead.


This tutorial shows how you can use the Severalnines Configurator for MySQL Replication to deploy a Multi-master replication setup, and install ClusterControl.

When the deployment is finished you have a set of tools to manage and monitor replication, as well as to add new slaves, and to perform failover.
You can choose:

  • if you wish also setup bi-directional replication between the masters
  • the number of …
[Read more]
New year & new blog

The new year is here and I have moved my (so far quite silent) blog to use WordPress and MySQL 5.5 GA.

Since I am using Ubuntu I downloaded a compressed tar archive. I installed it in a custom directory and for starting I wrote a little upstart script.

$ cat /etc/init/mysql-5.5.conf
start on startup
stop on shutdown

env basedir=/opt/mysql/mysql-5.5
env defaults=/etc/mysql-5.5/my.cnf

script
        cd $basedir
        $basedir/bin/mysqld_safe --defaults-file=$defaults
end script

In wp-config.php I have set:

define('DB_HOST', …
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Oracle TechCast Live: "MySQL 5.5 Does Windows"

Interested in MySQL on Windows? Join our next Oracle TechCast Live on Tuesday January 11th at 10.00 am PT! MySQL Product Manager Mike Frank will then tell you all about the major MySQL 5.5 performance gains on Windows.

 

In case you're not familiar with the Oracle TechCast Live events, they're akin to online "fireside chats" with experts about new tools, technologies and trends in application development. They also include live Q&A sessions, and you can ask questions via Twitter & Facebook. You can check out a few archived sessions here.

 

Get ready to ask your questions to Mike! …

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Oracle TechCast Live: "MySQL 5.5 Does Windows"

Interested in MySQL on Windows? Join our next Oracle TechCast Live on Tuesday January 11th at 10.00 am PT! MySQL Product Manager Mike Frank will then tell you all about the major MySQL 5.5 performance gains on Windows.

 

In case you're not familiar with the Oracle TechCast Live events, they're akin to online "fireside chats" with experts about new tools, technologies and trends in application development. They also include live Q&A sessions, and you can ask questions via Twitter & Facebook. You can check out a few archived sessions here.

 

Get ready to ask your questions to Mike! …

[Read more]
A step by step guide to upgrading to MySQL 5.5

MySQL 5.5 has created a lot of hype and its not just hype, there are major performance enhancements not only in the MySQL server itself but in the newer InnoDB plugin shipped with MySQL 5.5. That's exactly the reason why I have myself upgraded to MySQL 5.5 (The server running this blog run MySQL 5.5). Now since I haven't come across a guide to help in upgrading to MySQL 5.5, I thought why not make one myself