The Percona Kubernetes Operator for Percona XtraDB Cluster(PXC) comes with ProxySQL as part of the deal. And to be honest, the behavior of ProxySQL is pretty much the same as in a regular non-k8s deployment of it. So why bother to write a blog about it? Because what happens around ProxySQL in the context of the operator is actually interesting.

ProxySQL is deployed on its own POD (that can be scaled as well as the PXC Pods can). Each ProxySQL Pod has its own ProxySQL Container and a sidecar container. If you are curious, you can find out which node holds the pod by running

kubectl describe pod cluster1-proxysql-0 | grep Node:
Node: ip-192-168-37-111.ec2.internal/192.168.37.111

Login into and ask for the running containers. You will see something like this:

[root@ip-192-168-37-111 ~]# docker ps | grep -i proxysql …

In real life, there are frequent cases where getting a running application to work correctly is strongly dependent on consistent write/read operations. This is no issue when using a single data node as a provider, but it becomes more concerning and challenging when adding additional nodes for high availability and/or read scaling. 

In the MySQL dimension, I have already described it here in my blog Dirty Reads in High Availability Solution.

We go from the most loosely-coupled database clusters with primary-replica async replication, to the fully tightly-coupled database clusters with NDB Cluster (MySQL/Oracle).

Adding components like ProxySQL to the architecture can, from one side, help in improving high availability, and from the other, it can amplify and randomize the negative effect of …

Long months of the pandemic lockdown have brought to life many great online events enabling the MySQL community to get together and stay informed about the very recent developments and innovations available to MySQL users. It isn’t over yet! Next Thursday, June 4th, Percona & ProxySQL are co-hosting the ProxySQL Tech Talks with Percona virtual meetup covering ProxySQL, MySQL and Percona XtraDB Cluster.

The attendees are invited to participate in the two-hour deep-dive event with plenty of time for questions and answers (we will have two 40-minute sessions + 20 minutes allocated for Q&A). Get prepared, come with your burning questions and true war stories – we’ll have our speakers answer and comment on them! And here come the speakers:

• René Cannaò, ProxySQL author and CEO of ProxySQL …

Percona has enforced stronger security in Percona XtraDB Cluster (PXC) 8, but this requires some attention during the rollout of the new server version, so let see the why and what.

In PXC there are two different kinds of traffic: client-server exchange (ie: application traffic), and replication traffic. The latter refers to any SST/IST, write-set, and other service messages the nodes exchange.

In PXC 5.7 it is possible to activate SSL encryption by enabling the variable pxc-encrypt-cluster-traffic by following the instructions.

In PXC 8, we choose to enable encryption by default on all replication traffic, to have the highest out-of-box security enforcement.

While this is an obvious …

Percona XtraDB Cluster 8.0 comes with an upgraded Galera 4.0 library, which provides a new feature – streaming replication. Let’s review what it is and when it might be helpful.

Previous versions of Percona XtraDB Cluster with Galera 3.x had a limitation in how big transactions are handled.

Let’s review the performance under sysbench-tpcc workload when in parallel we update a big update on a table that is even non-related to the tables in the primary workload.

Without Streaming Replication

Let’s run two workloads.

1. sysbench-tpcc workload with 1 sec resolution
2. In parallel run UPDATE oltp.sbtest SET k=k+1 LIMIT 1000000

Running update:

mysql> update sbtest1 set k=k+1 limit 1000000;
Query OK, 1000000 rows affected (34.48 sec)
Rows matched: 1000000  Changed: …

I was testing the latest Percona XtraDB Cluster 8.0 (PXC) release which has the Galera 4 plugin, and I would like to share my experiences and thoughts on the Streaming Replication feature so far.

What Is Streaming Replication, in One Sentence?

In Galera 4, the large transaction could split into smaller fragments, and even before it got committed these fragments have been replicated to the other nodes and have already started the certification and apply process.

The manual describes all the pros and cons, but let’s see how it works. I have created a table with 10M rows and I am going to run some large updates on that.

First I have run the updates without Streaming Replication, and because it is disabled by …

As Alkin and Ramesh have shown us in their Testing Percona XtraDB Cluster 8.0 with DBdeployer post, it is now possible to easily deploy an environment to test the features provided by the brand new release of Percona XtraDB Cluster 8.0.

We have also worked on creating a testing environment available for those that use Vagrant instead. Be it that it’s what you are used to working with, or that you want a proper VM for each instance, in particular, you can use the following commands to easily deploy a three-node cluster.

Requirements

Vagrant runs in Linux, Mac OS, and Windows, you just need to have the packages installed. Visit …

In the light of support for Percona XtraDB Cluster (PXC), the DBdeployer anniversary, and the newly released Percona XtraDB Cluster 8.0, I’m happy to announce that Giuseppe Maxia has recently updated DBdeployer to support Percona XtraDB Cluster 8.0.

We at Percona, with my colleague Ramesh Sivaraman, have tested and deployed Percona XtraDB Cluster (PXC) 8.0.18  successfully using DBdeployer.

What is DBdeployer and How Do You …

April 29, 2020 – Percona is pleased to announce the release of Percona XtraDB Cluster 8.0. This release, based on Percona Server for MySQL 8.0 and Galera 4, brings together the best features of these and other products to deliver an open-source high availability MySQL solution that helps enterprises minimize unexpected downtime and data loss, improve data security, and ensure data integrity of your database environments supporting your critical business applications in the most demanding public, private, and hybrid cloud environments.

Percona XtraDB Cluster 8.0 enables enterprises to improve data security and ensure data integrity with new encryption and streaming replication features. …

In this blog post I would like to give an overview of the most common failover scenarios and operations when using MySQL Group Replication 8.0.19 (aka GR) and Percona XtraDB Cluster 8 (PXC) (which is based on Galera), and explain how each technology handles each situation. I have created a three-node cluster with Group Replication using a single Primary and a three-node PXC, both with default settings. I am also going to use ProxySQL to interface with both clusters.

In both clusters, the name of the nodes are mysql1, mysql2,  and mysql3. In Group Replication the Primary node is where the writes go if we are using single primary configuration. In PXC, I will use the same term as well and will call the node Primary where I am sending the writes. Just to note, in PXC there is no concept of primary node, …