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Search Results for: pt variable

Using per-query variable statements in Percona Server

Percona Server has implemented per-query variable statement support in version 5.6.14-62.0. This feature provides the ability to set variable values only for a certain query, after execution of which the previous values will be restored. …

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InnoDB adaptive flushing in MySQL 5.6: checkpoint age and io capacity

In MySQL 5.6 InnoDB has a dedicated thread (page_cleaner) that’s responsible for performing flushing operations. Page_cleaner performs flushing of the dirty pages from the buffer pool based on two factors: – access pattern  –  the …

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MySQL 5.6 Configuration Optimization Webinar, Sept. 25

This Wednesday in our next webinar I’ll share how to configure a better-performing MySQL 5.6 server. You’ll lean a practical approach to generating a sensible configuration file that sets what is needed and omits what …

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InnoDB performance optimization basics (redux)

I recently stumbled upon a post that Peter Zaitsev published back in 2007 titled “Innodb Performance Optimization Basics.” It’s a great post and reading it inspired me to examine what’s changed in the nearly six …

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Amazon RDS with MySQL 5.6 – Configuration Variables

One longstanding complaint I have heard for the past several years, and still hear today, is that Amazon’s Relational Database Service (RDS) does not allow the configuration flexibility as running MySQL in an ec2 instance. …

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Percona Toolkit 2.2.2 released; bug fixes include pt-heartbeat & pt-archiver

During the Percona Live MySQL Conference & Expo 2013 the week before last, we quietly released Percona Toolkit 2.2.2 with a few bug fixes: pt-archiver –bulk-insert may corrupt data pt-heartbeat –utc –check always returns 0 …

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MySQL 5.6.10 Optimizer Limitations: Index Condition Pushdown

While preparing the webinar I will deliver this Friday, I ran into a quite interesting (although not very impacting) optimizer issue: a “SELECT *” taking half the time to execute than the same “SELECT one_indexed_column” …

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MySQL optimizer: ANALYZE TABLE and Waiting for table flush

The MySQL optimizer makes the decision of what execution plan to use based on the information provided by the storage engines. That information is not accurate in some engines like InnoDB and they are based …

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MySQL 5.5 and MySQL 5.6 default variable values differences

As the part of analyzing surprising MySQL 5.5 vs MySQL 5.6 performance results I’ve been looking at changes to default variable values. To do that I’ve loaded the values from MySQL 5.5.30 and MySQL 5.6.10 …

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Sphinx search performance optimization: attribute-based filters

One of the most common causes of a poor Sphinx search performance I find our customers face is misuse of search filters. In this article I will cover how Sphinx attributes (which are normally used …

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