In this blog post, we’ll look at a transaction replay anomaly in Percona XtraDB Cluster.

Introduction

Percona XtraDB Cluster/Galera replays a transaction if the data is non-conflicting but, the transaction happens to have conflicting locks.

Anomaly

Let’s understand this with an example:

• Let’s assume a two-node cluster (node-1 and node-2)
• Base table “t” is created as follows:

create database test;
use test;
create table t (i int, c char(20), primary key pk(i)) engine=innodb;
insert into t values (1, 'abc'), (2, 'abc'), (4, 'abc');
select * from t;
mysql> select * from t;
+---+------+
| i | c |
+---+------+
| 1 | abc |
| 2 | abc |
| 4 | abc |
+---+------+

• node-2 starts runs a transaction (trx-2):
…

In this blog post, we’ll look at how increasing the fc_limit can affect SELECT latency.

Introduction

Recent Percona XtraDB Cluster optimizations have exposed fc_limit contention. It was always there, but was never exposed as the Commit Monitor contention was more significant. As it happens with any optimization, once we solve the bigger contention issues, smaller contention issues start popping up. We have seen this pattern in InnoDB, and Percona XtraDB Cluster is no exception. In fact, it is good because it tells us that we are on the right track.

If you haven’t yet checked the performance blogs, then please visit here and …

In this blog, we’ll look at how to achieve better-than-linear scaling.

Scalability is the capability of a system, network or process to handle a growing amount of work, or its potential to be enlarged to accommodate that growth. For example, we consider a system scalable if it is capable of increasing its total output under an increased load when resources (typically hardware) are added: https://en.wikipedia.org/wiki/Scalability.

It is often accepted as a fact that systems (in particular databases) can’t scale better than linearly. By this I mean when you double resources, the expected performance doubles, at best (and often is less than doubled).  

We can attribute this assumption to Amdahl’s law (https://en.wikipedia.org/wiki/Amdahl%27s_law), and later …

The MariaDB project is pleased to announce the immediate availability of MariaDB 5.5.55 Stable (GA), MariaDB Galera Cluster 5.5.55 Stable (GA) and MariaDB Connector/J 2.0.0 RC. See the release notes and changelogs for details. Download MariaDB 5.5.55 Release Notes Changelog What is MariaDB 5.5? MariaDB APT and YUM Repository Configuration Generator Download MariaDB Galera Cluster […]

The post MariaDB 10.3.0 Alpha, 5.5.55 Stable, and Connector/J 2.0.0 RC now available appeared first on MariaDB.org.

The MySQL team is constantly improving and innovating the product… this time, after having put particular attention to DBAs and operators with Group Replication & InnoDB Cluster,  let’s have a look to what we can also bring to developers.

Let’s start with the following challenge:

Add 5 books from scratch with all their metadata (authors, isbn, edition, year, …) in last than 5 minutes using only MySQL Shell in command line !

Do you thinks this is not possible ? Check the video below:

Amazing isn’t it ?

If you want to learn more about this, please attend Mike Zinner & Alfredo Kojima’s session at Percona Live next week:

This quick post demonstrates using Percona Server for MySQL in Docker Swarm with some new authentication provisioning practices.

Some small changes to the startup script for the Percona-Server container image allows us to specify a file that contains password values to set as our root user’s secret. “Why do we need this functionality,” I hear you cry? When we use an environment variable, it’s not terribly hard to locate the value to which someone has set as their database root password. Environment variables are not well suited for sensitive data. We preach against leaving our important passwords in easy to reach places. So moving towards something more secure whilst retaining usability is desirable. …

In this blog post, we’ll look at a feature that recently added to Percona XtraDB Cluster 5.7.16, that makes it easier to configure Percona XtraDB Cluster SSL for all related communications. It uses mode “encrypt=4”, and configures SSL for both IST/Galera communications and SST communications using the same SSL files. “encrypt=4” is a new encryption mode added in Percona XtraDB Cluster 5.7.16 (we’ll cover it in a later blog post).

If this option is used, this will override all other Galera/SST SSL-related file options. This is to ensure that a consistent configuration is applied. Using this option also means that the Galera/SST communications are …

In this blog, we’ll look at how to setup and troubleshoot the Percona PAM authentication plugin.

We occasionally get requests from our support clients on how to get Percona Server for MySQL to authenticate with an external authentication service via LDAP or Active Directory. However, we normally do not have access to client’s infrastructure to help troubleshoot these cases. To help them effectively, we need to setup a testbed to reproduce their issues and guide them on how to get authentication to work. Fortunately, we only need to install Samba to provide an external authentication service for both LDAP and AD.

In this article, I will show you how to (a) compile and install Samba, (b) create a domain environment with Samba, (c) add users and groups to this domain and (d) get Percona Server …

In this tutorial, we are going to guide you through the entire process of creating a 3 node InnoDB cluster in Oracle Public Cloud (OPC). We will address each of the steps, from the initial configuration and setup of the OPC IaaS resources to the InnoDB cluster creation and setup.…

ClusterControl allows you to easily manage your database infrastructure on premise or in the cloud. With in-depth support for technologies like Galera Cluster for MySQL and MariaDB setups, you can truly automate mixed environments for next-level applications.

Since the launch of ClusterControl in 2012, we’ve experienced growth in new industries with customers who are benefiting from the advancements ClusterControl has to offer - in particular when it comes to Galera Cluster for MySQL.

In addition to reaching new highs in ClusterControl demand, this past year we’ve doubled the size of our team allowing us to continue to provide even more improvements to ClusterControl.

Take a look at this infographic for our top Galera Cluster for MySQL resources and information about how ClusterControl works with Galera Cluster.

Tags:  galera …