XtraDB Cluster

Galera Cache (gcache) is finally recoverable on restart

Gcache

This post describes how to recover Galera Cache (or gcache) on restart.
Recently Codership introduced (with Galera 3.19) a very important and long awaited feature. Now users can recover Galera cache on restart.
Need
If you gracefully shutdown cluster nodes one after another, with some lag time between nodes, then the last node to shutdown holds the latest […]

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All You Need to Know About GCache (Galera-Cache)

GCache

This blog discusses some important aspects of GCache.
Why do we need GCache?
Percona XtraDB Cluster is a multi-master topology, where a transaction executed on one node is replicated on another node(s) of the cluster. This transaction is then copied over from the group channel to Galera-Cache followed by apply action.
The cache can be discarded immediately once the […]

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Percona XtraDB Cluster 5.7.14-26.17 GA is now available

wsrep-stages

This Percona XtraDB Cluster 5.7.14-26.17 GA release is dedicated to the memory of Federico Goncalvez, our colleague with Percona’s Uruguayan team until his tragic death on September 6, 2016.
Fede, we miss you.
Percona announces the first general availability (GA) release in the Percona XtraDB Cluster 5.7 series on September 29, 2016. Binaries are available from the downloads area or our […]

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Percona XtraDB Cluster 5.7.12 RC1 is now available

wsrep-stages

Percona announces the first release candidate (RC1) in the Percona XtraDB Cluster 5.7 series on August 9, 2016. Binaries are available from the downloads area or our software repositories.
Percona XtraDB Cluster 5.7.12-5rc1-26.16 is based on the following:

Percona Server 5.7.12
Galera Replicator 3.16

This release includes all changes from upstream releases and the following:
New Features

PXC Strict Mode: Use the pxc_strict_mode variable […]

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Percona XtraDB Cluster on Ceph

Ceph

This post discusses how XtraDB Cluster and Ceph are a good match, and how their combination allows for faster SST and a smaller disk footprint.
My last post was an introduction to Red Hat’s Ceph. As interesting and useful as it was, it wasn’t a practical example. Like most of the readers, I learn about […]

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Galera warning “last inactive check”

MySQL high availability

In this post, we’ll discuss the Galera warning “last inactive check” and what it means.
Problem
I’ve been working with Percona XtraDB Cluster quite a bit recently, and have been investigating various warnings. I came across this one today:
[Warning] WSREP: last inactive check more than PT1.5S ago (PT1.51811S), skipping check
This warning is related to the evs.inactive_check_period […]

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Galera Error Failed to Report Last Committed (Interrupted System Call)

In this blog, we’ll discuss the ramifications of the Galera Error Failed to Report Last Committed (Interrupted System Call).
I have recently seen this error with Percona XtraDB Cluster (or Galera):
[Warning] WSREP: Failed to report last committed 549684236, -4 (Interrupted system call)
It was posted in launchpad as a bug in 2013: https://bugs.launchpad.net/percona-xtradb-cluster/+bug/1434646
My colleague Przemek replied, […]

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Better high availability: MySQL and Percona XtraDB Cluster with good application design

High Availability
Have you ever wondered if your application should be able to work in read-only mode? How important is that question?
MySQL seems to be the most popular database solution for web-based products. Most typical Internet application workloads consist of many reads, with usually few writes. There are exceptions of course – MMO games for […]

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Playing with Percona XtraDB Cluster in Docker

Like any good, thus lazy, engineer I don’t like to start things manually. Creating directories, configuration files, specify paths, ports via command line is too boring. I wrote already how I survive in case when I need to start MySQL server (here). There is also the MySQL Sandbox which can be used for the […]

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MaxScale: A new tool to solve your MySQL scalability problems

Ever since MySQL replication has existed, people have dreamed of a good solution to automatically split read from write operations, sending the writes to the MySQL master and load balancing the reads over a set of MySQL slaves. While if at first it seems easy to solve, the reality is far more complex.
First, the […]

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