April 24, 2014

How Percona Server handles data corruption more gracefully

I got a question a while ago about how Percona Server handles corrupted data more gracefully than the standard MySQL server from Oracle. The short version is that it won’t crash the whole server. With standard MySQL from Oracle, if any page of data in InnoDB is found to be corrupt, the entire instance will […]

Data Corruption, DRBD and story of bug

Working with customer, I faced pretty nasty bug, which is actually not rare situation , but in this particular there are some lessons I would like to share. The case is pretty much described in bug 55981, or in pastebin. Everything below is related to InnoDB-plugin/XtraDB, but not to regular InnoDB ( i.e in MySQL […]

Recovering Innodb table Corruption

Assume you’re running MySQL with Innodb tables and you’ve got crappy hardware, driver bug, kernel bug, unlucky power failure or some rare MySQL bug and some pages in Innodb tablespace got corrupted. In such cases Innodb will typically print something like this: InnoDB: Database page corruption on disk or a failed InnoDB: file read of […]

Mail clients and Databases

I get a lot of mail and I prefer to store it for long time if not forever. With modern hard disk sizes it should not be problem at all, but because of how mailing programs are written it causes a lot of problems. I’ve tried a lot of programs – Kmail, Evolution, Thunderbird on […]

8 common (but deadly) MySQL operations mistakes and how to avoid them

January 22 I gave a presentation on “How to Avoid Common (but Deadly) MySQL Operations Mistakes” for Percona MySQL Webinars. If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions. I answered as many as we […]

High-availability options for MySQL, October 2013 update

The technologies allowing to build highly-available (HA) MySQL solutions are in constant evolution and they cover very different needs and use cases. In order to help people choose the best HA solution for their needs, we decided, Jay Janssen and I, to publish, on a regular basis (hopefully, this is the first), an update on […]

How to move the InnoDB log sequence number (LSN) forward

This post focuses on the problem of the InnoDB log sequence number being in the future. Preface: What is an InnoDB log sequence number? The Log sequence number (LSN) is an important database parameter used by InnoDB in many places. The most important use is for crash recovery and buffer pool purge control. Internally, the InnoDB […]

Percona Server 5.6.13-60.5 third Release Candidate is now available

Percona is glad to announce the third Release Candidate of Percona Server 5.6.13-60.5 (downloads are available here and from the Percona Software Repositories). The final release is almost ready. Thank you to everyone who has been testing and filing bugs. You’ve been a big help and we can’t wait for you to see the fantastic […]

Migrating between MySQL schemas with Percona Xtrabackup

Recently, I was working with a client that asked about using Percona Xtrabackup to take a snapshot of a particular MySQL schema and then reload it with a different schema name on the same server.  It caught me off guard because I’d never really thought about it – typically, I’ve used Xtrabackup simply to clone […]

Percona Server 5.5.30-30.2 rerelease fixes non-restart issue

In our last 5.5 series release of Percona Server, we included a regression in the RPM packaging that prevented the server from restarting following an upgrade — instead, the server would remain stopped after the upgrade was completed regardless of its state before updating. This caused some problems for some users, especially if automatic upgrading was configured […]