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The second MySQL tutorial session at Oracle Open World was “MySQL Group Replication in a Nutshell” by MySQL Community Manager Frederic Descamps. This is succinctly described as:

“Multi-master update anywhere replication for MySQL with built-in conflict detection and resolution, automatic distributed recovery, and group membership.”

MySQL Group Replication (GR) is a virtually synchronous replication solution which is an integral component of MySQL InnoDB Cluster announced at the MySQL keynote. You can download a labs version of MySQL InnoDB cluster which includes three components.

• MySQL Router …

Somebody recently asked, what they had to do, if they wanted to move their InnoDB-Logfiles back to the datadir. As a challenge, the servers were part of a Galera Cluster.

My first thought was:

The problem is not the Galera Cluster itself, it is the rsync-SST (wsrep_sst_method = rsync) that could cause trouble and destroy your InnoDB-Logfiles, by simply overwriting or deleting them.

So I tried to confirm my thought and realised, I was wrong. This works anyway, because the node just takes the dataset from the other node. (The backup plan was ready now.)

Preferably, the cluster does an IST, where it only fetches the missing write sets. This way you do not have the danger of losing the …

General query logs and slow query logs remain one of the most popular sources of auditing and diagnostic information in MySQL databases. Customers often ask about the cost of general and slow query logging so I went googling for existing research I could point them to. The data I found was not quite what I hoped for, which is why I decided to do some more testing.

Introduction Logging overhead is an obvious thing and it has been the topic of many blog posts before this one. Sure enough, my Google search returned multiple articles, however I wasn't fully satisfied the findings.
Perhaps the topic is so obvious that DBAs don't revisit it very often. In any case, most of the articles I found were several years old and that presents a few issues:

1. Most of the tests were run on MySQL 5.0 or 5.1.
2. Database hardware isn't what it used to be, which changes the perspective on database performance bottlenecks. …

    Recently we went through an exercise where we moved all of our database masters between data centers. We planned on doing this online with minimal user impact. Obviously when performing this sort of action there are a variety of considerations such as cache consistency and other pieces of shared state in stores like HBase, but the focus of this post will be primarily on MySQL.

    During this move we had a number of constraints. As mentioned above this was to be online when serving production traffic with minimal user impact. In aggregate we service hundreds of thousands of database queries per second. Additionally we needed to encrypt all data transferring between data centers. MySQL replication supports encryption, but connections to the servers themselves present several challenges. Specifically, from a performance standpoint the handshake to establish a connection across a WAN can impact latency if …

A stripped down version of TokuDB is running on MySQL 8.0.

mysql> select @@version\G; *************************** 1. row *************************** @@version: 8.0.0-dmr-debug 1 row in set (0.00 sec)
mysql> show create table test.t\G; *************************** 1. row ***************************        Table: t Create Table: CREATE TABLE `t` (   `id` int(11) NOT NULL,   PRIMARY KEY (`id`) ) ENGINE=TokuDB DEFAULT CHARSET=latin1 1 row in set (0.00 sec)
mysql> show engines\G; *************************** 6. row ***************************       Engine: TokuDB      Support: YES      Comment: Percona TokuDB Storage Engine with Fractal Tree(tm) Technology Transactions: YES           XA: YES   Savepoints: YES
mysql> create table test.t (id int primary key) engine=tokudb; Query OK, 0 rows affected (0.08 …

Today was the first day of sessions at Percona Live Europe 2016, and it was packed with exciting talks and important information on open source databases. Some of the most anticipated talks are those that cover what to expect in MySQL 8.0.

One of those talks was given by Oracle’s Manyi Lu, Director of Software Development. She discussed MySQL 8.0: what’s new in Optimizer.

In her talk, Manyi discussed what we could look forward to in MySQL 8.0’s optimizer. There are substantial improvements in the optimizer in MySQL 5.7 and MySQL 8.0. Most noticeably, users can now combine relational data with NoSQL using the new JSON features. MySQL also now supports functional indexes through generated columns. …

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 …

Overview

MySQL 8.0 comes with the new design of INFORMATION_SCHEMA subsystem. The blog MySQL 8.0: Improvements to Information_schema provides an overview of the improvements we made. This blog focuses mainly to demonstrate performance of the INFORMATION_SCHEMA in MySQL 8.0, giving us an idea on the kind of performance gain that one can expect.…

In the previous post, we looked into the basics of running MySQL containers on multiple Docker hosts managed by Swarm Mode, a native orchestration tool comes with Docker 1.12. However, at the time of writing, Docker Engine Swarm Mode does not support other networking plugins like Calico, Weave or Flannel. If we’d like to run any of these, we must run it outside of Docker Swarm mode and use other tools for orchestration e.g, Kubernetes, Mesos or Docker Swarm.

In this blog post, we are going to look into other networking drivers that support multi-host networking to best fit our MySQL setups. We are going to deploy MySQL Replication on top of three Docker hosts via Calico’s driver on multi-host networking. Weave and Flannel will be covered in the upcoming blog posts.

Calico …

In this blog post, we’ll look at MySQL 8.0 general tablespaces.

Introduction

MySQL 8.0 (the DMR version is available now) has two great features (among others):

1. The new data dictionary completely removed *.frm files, which is great
2. The ability to create a tablespace and assign a group of tables to it (originally introduced in 5.7).

With those two options, we can use MySQL for creating multi-tenant environments with a “schema per customer” approach.

Schema per Customer with MySQL 8.0

Using schema per customer with older MySQL versions presents issues  … namely the number of files. (I’ve described …