November 21, 2014

Galera Flow Control in Percona XtraDB Cluster for MySQL

Last week at Percona Live, I delivered a six-hour tutorial about Percona XtraDB Cluster (PXC) for MySQL.  I actually had more material than I covered (by design), but one thing I regret we didn’t cover was Flow control.  So, I thought I’d write a post covering flow control because it is important to understand. What […]

Understanding Multi-node writing conflict metrics in Percona XtraDB Cluster and Galera

I have addressed previously how multi-node writing causes unexpected deadlocks in PXC, at least, it is unexpected unless you know how Galera replication works.  This is a complicated topic and I personally feel like I’m only just starting to wrap my head around it. The magic of Galera replication The short of it is that Galera […]

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 […]

Multi-Valued INSERTs, AUTO_INCREMENT & Percona XtraDB Cluster

A common migration path from standalone MySQL/Percona Server to a Percona XtraDB Cluster (PXC) environment involves some measure of time where one node in the new cluster has been configured as a slave of the production master that the cluster is slated to replace. In this way, the new cluster acts as a slave of […]

Taking backups on Percona XtraDB Cluster (without stalls!)

I occasionally see customers who are taking backups from their PXC clusters that complain that the cluster “stalls” during the backup.  As I wrote about in a previous blog post, often these stalls are really just Flow Control.  But why would a backup cause Flow control? Most backups I know of (even Percona XtraBackup) take […]