Emergency

Author Archives: Jay Janssen

Optimizing PXC Xtrabackup State Snapshot Transfer

State Snapshot Transfer (SST) at a glance PXC uses a protocol called State Snapshot Transfer to provision a node joining an existing cluster with all the data it needs to synchronize.  This is analogous to …

Read More
 

PXC – Incremental State transfers in detail

IST Basics State transfers in Galera remain a mystery to most people.  Incremental State transfers (as opposed to full State Snapshot transfers) are used under the following conditions: The Joiner node reports Galera a valid …

Read More
 

Bypassing SST in Percona XtraDB Cluster with binary logs

In my previous post, I used incremental backups in Percona XtraBackup as a method for rebuilding a Percona XtraDB Cluster (PXC) node without triggering an actual SST. Practically this reproduces the SST steps, but it …

Read More
 

Bypassing SST in Percona XtraDB Cluster with incremental backups

Beware the SST In Percona XtraDB Cluster (PXC) I often run across users who are fearful of SSTs on their clusters. I’ve always maintained that if you can’t cope with a SST, PXC may not …

Read More
 

TOI wsrep_RSU_method in PXC 5.6.24 and up

I noticed that in the latest release of Percona XtraDB Cluster (PXC), the behavior of wsrep_OSU_method changed somewhat.  Prior to this release, the variable was GLOBAL only, meaning to use it you would:

This …

Read More
 

Is 80% of RAM how you should tune your innodb_buffer_pool_size?

It seems these days if anyone knows anything about tuning InnoDB, it’s that you MUST tune your innodb_buffer_pool_size to 80% of your physical memory. This is such prolific tuning advice, it seems engrained in many …

Read More
 

Testing backup locks during Xtrabackup SST on Percona XtraDB Cluster

Background on Backup Locks I was very excited to see Backup locks support in release notes for the latest Percona XtraDB Cluster 5.6.21 release. For those who are not aware, backup locks offer an alternative to FLUSH …

Read More
 

Streamlined Percona XtraDB Cluster (or anything) testing with Consul and Vagrant

Introducing Consul I’m always interested in what Mitchell Hashimoto and Hashicorp are up to, I typically find their projects valuable.  If you’ve heard of Vagrant, you know their work. I recently became interested in a …

Read More
 

Auto-bootstrapping an all-down cluster with Percona XtraDB Cluster

One new feature in Percona XtraDB Cluster (PXC) in recent releases was the inclusion of the ability for an existing cluster to auto-bootstrap after an all-node-down event.  Suppose you lose power on all nodes simultaneously or …

Read More
 

(More) Secure local passwords in MySQL 5.6 and up

I log into a lot of different servers running MySQL and one of the first things I do is create a file in my home directory called ‘.my.cnf’ with my credentials to that local mysql …

Read More