May 24, 2013

Replication checksums in MySQL 5.6

MySQL 5.6 has an impressive list of improvements. Among them, replication checksums caught my attention as it seems that many people misunderstand the real added value of this new feature. I heard people think that with replication checksums, data integrity between the master and its replicas is now enforced. As we’ll see, it’s not that [...]

How to create/restore a slave using GTID replication in MySQL 5.6

MySQL 5.6 is GA! Now we have new things to play with and in my personal opinion the most interesting one is the new Global Transaction ID (GTID) support in replication. This post is not an explanation of what is GTID and how it works internally because there are many documents about that: http://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html One [...]

New Keynote Speakers and Sponsors and Applications Open for DotOrg Pavilion for Percona Live MySQL Conference and Expo

I’m pleased to announce the first of the Percona Live MySQL Conference and Expo 2013 keynote speakers and new sponsors including Amazon Web Services, Google, Clustrix, Scalebase, PalominoDB, Database Trends & Applications, and Linux Journal. We are also now accepting applications for the DotOrg Pavilion. Also, nominations are now being accepted for the 2013 MySQL [...]

DotOrg Pavilion and MySQL Community Awards at Percona Live MySQL Conference and Expo 2013

Percona Live MySQL Conference and Expo 2013 – the largest MySQL Conference event of the year is getting close and we’re now announcing two community activities which are going to happen at this event. Call of DotOrg Pavilion exhibitors is open – DotOrg pavilion is a free expo hall space for non commercial projects relevant [...]

Percona Toolkit Webinar followup Q&A

First, a thank you to everyone who attended the webinar Today, I appreciate your time and nice comments. As promised, here are answers to questions that couldn’t be answered during the talk:   Q: How do you install the tools? The manual has full details, but it’s important to know that the latest release for [...]

Minimizing Downtime from Lengthy AWS Outages

Well, it happened again…  Another lengthy EBS outage in the US-East region impacted several sites across the net.  While failures like this are rare, they can be quite costly and translate into headaches for the operations team when impact production systems for any length of time.  At Percona, we routinely help clients architect and deploy [...]

Automation: A case for synchronous replication

Just yesterday I wrote about math of automatic failover today I’ll share my thoughts about what makes MySQL failover different from many other components and why asynchronous nature of standard replication solution is causing problems with it. Lets first think about properties of simple components we fail over – web servers, application servers etc. We [...]

How to lag a slave behind to avoid a disaster

MySQL Replication is useful and easy to setup. It is used for very different purposes. For example: split read and writes run data mining or reporting processes on them disaster recovery Is important to mention that a replication server is not a backup by itself. A mistake on the master, for example a DROP DATABASE [...]

Why ALTER TABLE shows as two transactions in SHOW ENGINE INNODB STATUS

When executing an ALTER TABLE, InnoDB (and XtraDB) will create two InnoDB transactions: One transaction is created when the table being ALTERed is locked by the server. This will show up as something like “TABLE LOCK table `schema`.`table_name` trx id XXXX lock mode S” in SHOW ENGINE INNODB STATUS. Another is created when adding or [...]