Monthly Archives - November 2013

What does the ‘Incorrect key file for table’ error mean?

What does it mean if MySQL returns the ‘Incorrect key file for table’ error for one of my queries? The answer is complicated and depends on which storage engine is returning the error. We have debugged two cases which we describe here.
File system out of space
When running the random query generator, one of the […]

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MySQL encryption performance, revisited

This is part two on a two-part series on the performance implications of in-flight data encryption with MySQL. In the first part, I focused specifically on the impact of using MySQL’s built-in SSL support with some rather surprising results. Certainly it was expected that query throughput would be lower with SSL than without, but […]

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Percona Live London 2013 and Percona Live MySQL Conference & Expo 2014

Thanks to everyone who participated in Percona Live London 2013. We had a great event with nearly 20% higher attendance versus 2012. This year’s conference featured participation by representatives from Oracle including a compelling keynote by Tomas Ulin. The conference featured 10 tutorial sessions on Monday and 4 keynotes and 30 breakout sessions on […]

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MySQL & Sphinx: Register now for Nov. 20 Webinar

Sphinx is a free, open-source search server that integrates nicely with MySQL. It provides a fast, scalable, and pluggable search framework. The Sphinx engine possesses a variety of tools enabling you to customize how searching/indexing interacts with or becomes a part of your environment.
Join me and Sphinx Search CEO/CTO Andrew Aksyonoff, the founder and creative […]

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Drupal and MySQL Performance: Register now for Nov. 13 webinar

Drupal is one of the most popular open source CMS applications available – and it runs primarily on a MySQL backend.  Out of the box, the schema is well tuned and indexed.  However, there are some ways to tweak the default installation to get more out of the system right from start.  Similarly, there […]

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Incremental backups with log archiving for XtraDB

Percona Server 5.6.11-60.3 has introduced a new feature called Log Archiving for XtraDB. This feature makes copies of the old log files before they are overwritten, thus saving all the redo log for a write workload.
When log archiving is enabled, it duplicates all redo log writes in a separate set of files in addition […]

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How Percona tested Percona Server 5.6: A world premiere in advanced testing

8PM. One of the servers found a critical bug. Hop online and discuss, log bug. 10PM. Patch ready. 10:30PM. New build ready. 10:45PM. New RQG run initiated. This was by no means an uncommon sight during the months of testing that went into Percona Server 5.6, in fact it was commonplace.
At a certain point, […]

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QA: Advanced Option Combinatorics (Pairwise Testing): Combinatorial mysqld Option Test Case Generation

How do we ensure that, when we have 35+ testable option combinations for mysqld, we test each and every combination of them? For example: will a different innodb_log_file_size combined with more innodb_log_files_in_group and a modified innodb_fast_shutdown setting truly not affect Percona’s log archiving feature?
Most option-related bugs are caused by the setting of 1 or […]

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How to Extract All Running Queries (Including the Last Executed Statement) from a Core File?

This post builds on the How to obtain the “LES” (Last Executed Statement) from an Optimized Core Dump? post written about a year ago.
A day after that post was released, Shane Bester wrote an improved version, How to obtain all executing queries from a core file on his blog. Reading that post is key […]

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Put your MySQL Knowledge to Good Use with Tim Callaghan at Percona Live-London, November 12

Attending Percona Live in London next week?
Don’t miss the chance to hear Tokutek’s Vice President of Engineering, Tim Callaghan, discuss how to use your MySQL knowledge to become an instant MongoDB Guru and the advantages of using Fractal Tree&#174 indexes in MySQL and MongoDB. Tim will be speaking about these topics in two […]

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