In this blog I will provide answers to the questions and queries that some of you have raised during the webinar on Nov 17th.

I would like to say thank you to all of the audience who attended the talk on November 17, 2016. You can also check the recording and slides here.

Q. How is storage distribution done across the node?

A. Each node has independent storage and other resources. There is no sharing of resource. Only the write-sets are replicated.

Q. If write-set propagation fails in some manner is there any retry mechanism?

A. write-set are written to …

Join Percona’s Percona XtraDB Cluster Lead Software Engineer Krunal Bauskar for a webinar on Thursday, November 17, 2016, at 7:30 am PST on MySQL High Availability with Percona XtraDB Cluster 5.7.

Percona XtraDB Cluster 5.7 is our brand new MySQL 5.7 compatible Galera-based high availability (HA) solution. Whether you’re new to MySQL clustering technology, or experienced with Galera-based replication, this tutorial provides great insights into working with the software, …

Percona announces the new release of Percona XtraDB Cluster 5.6.32-25.17 on October 4, 2016. Binaries are available from the downloads area or our software repositories.

Percona XtraDB Cluster 5.6.32-25.17 is now the current release, based on the following:

• Percona Server 5.6.32-78.1
• Galera Replication library 3.17
• Codership wsrep API version 25

Bugs Fixed:

• Fixed DONOR …

Percona  announces the new release of Percona XtraDB Cluster 5.6 on September 15, 2016. Binaries are available from the downloads area or our software repositories.

Percona XtraDB Cluster 5.6.30-25.16.2 is now the current release, based on the following:

• Percona Server 5.6.30-76.3
• Galera Replication library 3.16
• Codership wsrep API version 25

This release provides a …

Some time ago, I published the article on AWS Aurora Benchmarking (AWS Aurora Benchmarking – Blast or Splash?), in which I analyzed the behavior of different solutions using synchronous replication in AWS environment. This blog follows up with some of the comments and suggestions I received regarding that post from the community and Amazon engineers.

I decided to perform another round of tests, keeping in mind comments and suggestions received.

I presented some of the results during the Percona conference in Santa Clara last April 2016. The following is the transposition that presentation, with more details.

Not interested in the preliminary descriptions? Go to the results section

Why new tests?

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 instance – but often the number of reads is much bigger then writes. So when your database infrastructure looses its ability to accept writes, either because traditional MySQL replication topology lost its master or Galera cluster lost its quorum, why would you want to the application to declare total …

This blog post explores the syncing options for an inconsistent MySQL slave of Galera cluster node using pt-table-sync

The post Fixing inconsistency on MySQL Slave of Galera Cluster first appeared on Change Is Inevitable.

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 cloning a slave in asynchronous replication:  you take a full backup of one node and copy it to the new one, while tracking the replication position of the backup.

PXC automates this process using scriptable SST methods.  The most common of these methods is the xtrabackup-v2 method which is the default in PXC 5.6.  Xtrabackup generally is more favored over other SST methods because it is non-blocking on the Donor node (the node contributing the backup).

The basic flow of this method is:

• The Joiner:
  • joins the cluster …

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 Galera GTID to the cluster
• The Donor node selected contains all the transactions the Joiner needs to catch up to the rest of the cluster in its Gcache
• The Donor node can establish a TCP connection to the Joiner on port 4568 (by default)

IST states

Galera has many internal node states related to Joiner nodes.  They currently are:

1. Joining
2. Joining: preparing for State Transfer
3. Joining: requested State Transfer
4. Joining: receiving State Transfer
5. Joining: State …

Thank you for attending my July 15 webinar, “Creating Best in Class Backup solutions for your MySQL environment.” Due to the amount of content we discussed and some minor technical difficulties faced near the end of webinar we have decided to cover the final two slides of the presentation along with the questions asked by attendees during the webinar via this blog post.

The slides are available for download. And you can watch the webinar in it’s entirety here.

The final two slides were about our tips for having a …