August 21, 2014

Disconnecting a replication slave is easier with MySQL 5.5+ (RESET SLAVE vs. RESET SLAVE ALL)

It’s not uncommon to promote a server from slave to master. One of the key things to protect your data integrity is to make sure that the promoted slave is permanently disconnected from its old master. If not, it may get writes from the old master, which can cause all kinds of data corruption. MySQL […]

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 […]

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. […]

Percona XtraDB Cluster 5.5.37-25.10 is now available

Percona is glad to announce the release of Percona XtraDB Cluster 5.5.37-25.10 on May 8, 2014. Binaries are available from the downloads area or from our software repositories. Based on Percona Server 5.5.37-35.0 including all the bug fixes in it, Galera Replicator 2.10 (including fixes in 2.9 and 2.10 milestones) and on wsrep API 25.10 […]

Doing a rolling upgrade of Percona XtraDB Cluster from 5.5 to 5.6

Overview Percona XtraDB Cluster 5.6 has been GA for several months now and people are thinking more and more about moving from 5.5 to 5.6. Most people don’t want to upgrade all at once, but would prefer a rolling upgrade to avoid downtime and ensure 5.6 is behaving in a stable fashion before putting all of […]

Percona Server 5.5.37-35.0 is now available

Percona is glad to announce the release of Percona Server 5.5.37-35.0 on May 6th, 2014 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.37, including all the bug fixes in it, Percona Server 5.5.37-35.0 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of the release […]

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 […]

Percona XtraDB Cluster 5.6.15-25.5 is now available

Percona is glad to announce the new release of Percona XtraDB Cluster 5.6 on March 20th 2014. Binaries are available from downloads area or from our software repositories. Based on Percona Server 5.6.15-63.0 including all the bug fixes in it, Galera Replicator 3.4 and on Codership wsrep API 25.5 is now the current General Availability […]

10 MySQL settings to tune after installation

When we are hired for a MySQL performance audit, we are expected to review the MySQL configuration and to suggest improvements. Many people are surprised because in most cases, we only suggest to change a few settings even though hundreds of options are available. The goal of this post is to give you a list […]