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Monthly Archives: February 2012

How to Monitor MySQL with Percona’s Nagios Plugins

In this post, I’ll cover the new MySQL monitoring plugins we created for Nagios, and explain their features and intended purpose. I want to add a little context. What problem were we trying to solve …

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Database Algorithms sin Pantalones

So there I was, gesticulating in front of the chalkboard, lecturing to 120 students. Topic: the beauty of advanced data structures. The door opens and the department chair walks up the aisle onto the stage …

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DBD::mysql 4.014 breaks pt-table-checksum 2.0

DBD::mysql 4.014 breaks pt-table-checksum 2.0.  The cause is unknown, but the effect is a lot of errors like: DBD::mysql::st execute failed: called with 2 bind variables when 6 are needed [for Statement “…” with ParamValues: …

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How to recover deleted rows from an InnoDB Tablespace

In my previous post I explained how it could be possible to recover, on some specific cases, a single table from a full backup in order to save time and make the recovery process more …

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How to convert MySQL’s SHOW PROFILES into a real profile

SHOW PROFILES shows how much time MySQL spends in various phases of query execution, but it isn’t a full-featured profile. By that, I mean that it doesn’t show similar phases aggregated together, doesn’t sort them …

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MySQL Meetups in North Carolina this week

A quick reminder. I’m speaking on two MySQL meetups in North Carolina this week. Tuesday,Feb 21 on Raleigh MySQL/PHP Meetup and when Wednesday, Feb 22 on Charlotte Queen City PHP Note the last meetup date …

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Why don’t our new Nagios plugins use caching?

In response to the release of our new MySQL monitoring plugins on Friday, one commenter asked why the new Nagios plugins don’t use caching. It’s worth answering in a post rather than a comment, because …

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MariaDB 5.3.4 benchmarks

MariaDB 5.3 has reached the release candidate milestone, and the 5.3 version promises a lot of new features and optimization (i.e in optimizer http://kb.askmonty.org/en/what-is-mariadb-53#query-optimizer). No surprise I wanted to check how all improvements affect general …

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Can we improve MySQL variable handling ?

MySQL Settings (also known as Server Variables) have interesting property. When you set variable in running server this change is not persisted in any way and server will be back to old value upon restart. …

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The relationship between Innodb Log checkpointing and dirty Buffer pool pages

This is a time-honored topic, and there’s no shortage of articles on the topic on this blog. I wanted to write a post trying to condense and clarify those posts, as it has taken me …

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