In preparing Percona Server 5.5.29 (not yet released, but soon), I filed MySQL bug 68045 (is marked private as it’s a security bug). This bug is in relation to the Oracle fix for CVE-2012-4414 and a problem I found with it. The MariaDB fix (which we incorporated into Percona Server 5.5.28-29.3) is not affected.
When the MariaDB team fixed CVE-2012-4414 they created a test case named rpl_mdev382.test which can be …
[Read more]Percona Toolkit 2.1.8
Percona Toolkit 2.1.8 was released today and the new version comes with some pretty cool news: Beta support for MySQL 5.6 (which as you might know is also in beta).
In addition to various bug fixes, Percona Toolkit 2.1.8 also offers beta support for Percona XtraDB Cluster (PXC). Version 2.1.8 continues the trend of solid bug fix releases, and all 2.1 users are encouraged to upgrade.
You can download Percona Toolkit 2.1.8 here. (More info on Percona Toolkit). Users who plan on running the tools on Percona XtraDB Cluster or MySQL 5.6 are advised to upgrade. …
[Read more]pt-stalk recipes: Gather forensic data about MySQL when a server problem occurs
It happens to us all from time to time: a server issue arises that leaves you scratching your head. That’s when Percona Toolkit’s pt-stalk comes into play, helping you diagnose the problem by capturing diagnostic data that helps you pinpoint what’s causing the havoc hitting your database.
From the documentation (http://www.percona.com/doc/percona-toolkit/pt-stalk.html):
pt-stalk watches for a trigger condition to become true, and then collects data to help in diagnosing problems. It is designed to run as a daemon with root privileges, so that you can diagnose intermittent problems that you cannot observe directly. You can also use it to execute a custom command, or to gather the data on demand without waiting for the trigger to happen. …
[Read more]How easy is it to identify and debug Percona XtraDB Cluster replication problem ?
If you are using PXC, you may have already seen in your datadirectory several log files starting with GRA_
Those files correspond to a replication failure. That means the slave thread was not able to apply one transaction. For each of those file, a corresponding warning or error message is present in the mysql error log file.
Those error can also be false positive like a bad DDL statement (DROP a table that doesn’t exists for example) and therefore nothing to worry about. However it’s always recommended to understand what’s is happening.
As the GRA files contain binlog events in ROW format representing the failed transaction this post explains how to proceed.
The first step to be able to analyze your GRA files is to add a
binlog header to the file.
You can download one here : …
Recently there have been discussions on several vulnerabilities in MySQL and closely related projects such as MariaDB and Percona Server. Usually we have inherited security fixes from MySQL when we have updated Percona Server to be based off a new Oracle MySQL release. In this case however, Oracle has been incredibly quiet.
We’ve been examining how these affect current Percona Server versions and will shortly be making security releases and more information available (we wish to ensure what we say is correct in regards to Percona Server).
As seems to often be the case, we already had a release in the pipeline – Percona Server 5.5.28-29.2 which contains many bug fixes that affect users (see our release notes). We’re going to still release 5.5.28-29.2 and shortly after we’ll make 5.5.28-29.3 available …
[Read more]I had a customer recently who needed to reduce their database size on disk quickly without a lot of messy schema redesign and application recoding. They didn’t want to drop any actual data, and their index usage was fairly high, so we decided to look for unused indexes that could be removed.
Collecting data
It’s quite easy to collect statistics about index usage in Percona Server (and others) using the User Statistics patch. By enabling ‘userstat_running’, we start to get information in the INFORMATION_SCHEMA.INDEX_STATISTICS table. This data collection does add some overhead to your running server, but it’s important to leave this running for a good long while to get a good dataset that is representative of as much of your workload as possible.
If you miss collecting index stats while some …
[Read more]The Web And PHP Magazine just published an article describing Percona XtraDB Cluster written by Liz van Dijk and Kenny Gryp. It is a pretty high-level introduction to the technology, so definitely give it a read if you’ve been wanting to give it a closer look.
Go to their website http://www.webandphp.com and download Issue number 9 for free!
On Monday I will deliver with Seppo Jaakola from Codership a tutorial on Percona XtraDB Cluster (Percona Server + Galera).
Already in London and you don’t know how to consume the hotel’s bandwidth ? If you attend this tutorial, you can download the Virtual Box appliance we will use during the session.
Two versions are available:
How to test them:
If you are interested by a great and revolutionary HA solution for MySQL or even if you already have some experience with PXC and/or Galera, I invite you to attend the tutorial I will deliver in Percona Live MySQL Conference London 2012 (PLUK2012), December 3rd : Percona XtraDB Cluster in a nutshell.
Small amount of theory and a lot of exercises and examples to really tame the beast that PXC is !
A Codership engineer will also be present and happy to help me answering your questions.
Note to attendees: please bring your laptop with a recent Virtual Box installed and enough free space to store 3 VMs (+/-2G per VM). As said …
[Read more]The Percona Toolkit team is happy to announce the release of Percona Toolkit version 2.1.6. This is the sixth stable release in the 2.1 series, and primarily a bug-fix release; We suggest that users upgrade to the latest version of the tools.
The complete list of changes is on the Launchpad milestone for 2.1.6, but here are some highlights the release:
Remember that if you need help with Percona Toolkit, we provide flat-fee, unlimited support services with rapid 24×7 response on a …
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