July 24, 2014

Semi-Sync replication performance in MySQL 5.7.4 DMR

I was interested to hear about semi-sync replication improvements in MySQL’s 5.7.4 DMR release and decided to check it out.  I previously blogged about poor semi-sync performance and was pretty disappointed from semi-sync’s performance across WAN distances back then, particularly with many client threads. The Test The basic environment of these tests was: AWS EC2 […]

Errant transactions: Major hurdle for GTID-based failover in MySQL 5.6

I have previously written about the new replication protocol that comes with GTIDs in MySQL 5.6. Because of this new replication protocol, you can inadvertently create errant transactions that may turn any failover to a nightmare. Let’s see the problems and the potential solutions. In short Errant transactions may cause all kinds of data corruption/replication […]

Benchmark: SimpleHTTPServer vs pyclustercheck (twisted implementation)

Github user Adrianlzt provided a python-twisted alternative version of pyclustercheck per discussion on issue 7. Due to sporadic performance issues noted with the original implementation in SimpleHTTPserver, the benchmarks which I’ve included as part of the project on github use mutli-mechanize library, cache time 1 sec 2 x 100 thread pools 60s ramp up time 600s […]

Introduction to the Percona Server Audit Log feature

Percona has developed an Audit Log feature that is now included in Percona Server since the recent 5.5 and 5.6 releases. This implementation is alternative to the MySQL Enterprise Audit Log Plugin: Percona re-implemented the Audit Plugin code as GPL as Oracle’s code was closed source. This post is a quick introduction to this plugin. […]

max_allowed_packet and binary log corruption in MySQL

The combination of max_allowed_packet variable and replication in MySQL is a common source of headaches. In a nutshell, max_allowed_packet is the maximum size of a MySQL network protocol packet that the server can create or read. It has a default value of 1MB (<= 5.6.5) or 4MB (>= 5.6.6) and a maximum size of 1GB. […]

Practical MySQL performance optimization: May 14 Webinar

Achieving the best possible MySQL Performance doesn’t have to be complicated. It’s all about knowing which tools are designed for the task at hand – along with some basic (yet often overlooked) best practices. Join me Wednesday, May 14 at 10 a.m. Pacific for a free webinar titled, “Practical MySQL performance optimization.” I’ll be sharing […]

GTIDs in MySQL 5.6: New replication protocol; new ways to break replication

One of the MySQL 5.6 features many people are interested in is Global Transactions IDs (GTIDs). This is for a good reason: Reconnecting a slave to a new master has always been a challenge while it is so trivial when GTIDs are enabled. However, using GTIDs is not only about replacing good old binlog file/position […]

Row-based replication, MySQL 5.6 upgrades and temporal data types

Whither your rollback plan? MySQL 5.6 upgrades are in full swing these days and knowing how to safely upgrade from MySQL 5.5 to 5.6 is important. When upgrading a replication environment, it’s important that you can build a migration plan that safely allows for your upgrade with minimal risk — rollback is often a very […]

How to identify and cure MySQL replication slave lag

Here on the Percona MySQL Support team, we often see issues where a customer is complaining about replication delays – and many times the problem ends up being tied to MySQL replication slave lag. This of course is nothing new for MySQL users and we’ve had a few posts here on the MySQL Performance Blog […]

ScaleArc: Real-world application testing with WordPress (benchmark test)

ScaleArc recently hired Percona to perform various tests on its database traffic management product. This post is the outcome of the benchmarks carried out by me and ScaleArc co-founder and chief architect, Uday Sawant. The goal of this benchmark was to identify ScaleArc’s overhead using a real-world application – the world’s most popular (according to […]