Recently I had the opportunity to test a storage device from ScaleFlux called CSD 2000. In this blog post, I will share the results of using it to run MySQL in comparison with an Intel device that had a similar capacity.

First of all, why do we need another storage device? Why is ScaleFlux any different?

The answer is simple; it gives us built-in compression and atomic writes. For many workloads, but especially for database-type workloads, these are very important features.

Because of built-in compression, we can store more data on the ScaleFlux device than on a similar device with the same capacity.

Because of atomic writes, we can disable InnoDB Double Write buffer which means less writes/fsync on the disk layer. This should give us a performance advantage against non-atomic drives.

I ran many different tests on different data sizes, with different …

Last year, I made the first post in a small series, which aimed to highlight unique features of Percona Server for MySQL, by discussing binlog_space_limit option.

Today, I am going to discuss another important type of log available in MySQL that is enhanced in Percona Server for MySQL – the slow query log. The reason why I am doing this is that although this extension has existed since the very early times of versions 5.1 (over 10 years ago!), many people are still unaware of it, which I see from time to time when working with Support customers.

Default Slow Log Inadequacy

How many times have you been wondering why, whilst reviewing slow query logs, the very same query occasionally runs way slower than usual? There may be many reasons for that, but the standard slow …

Usually one would expect that ALTER TABLE with ALGORITHM=COPY will be slower than the default ALGORITHM=INPLACE. In this blog post we describe the case when this is not so.

One of the reasons for such behavior is the lesser known limitation of ALTER TABLE (with default ALGORITHM=INPLACE) that avoids REDO operations. As a result, all dirty pages of the altered table/tablespace have to be flushed before the ALTER TABLE completion.

Some history

A long time ago, all “ALTER TABLE” (DDLs) operations in MySQL were implemented by creating a new table with the new structure, then copying the content of the original table to the new table, and finally renaming the table. During this operation the table was locked to prevent data inconsistency.

Then, for InnoDB tables, the new algorithms were introduced, which do not involve the full table copy and some operations do not apply the table level lock – first the online …

When connecting to a local MySQL instance, you have two commonly used methods: use TCP/IP protocol to connect to local address –  “localhost” or 127.0.0.1  – or use Unix Domain Socket.

If you have a choice (if your application supports both methods), use Unix Domain Socket as this is both more secure and more efficient.

How much more efficient, though?  I have not looked at this topic in years, so let’s see how a modern MySQL version does on relatively modern hardware and modern Linux.

Benchmarking  TCP/IP Connection vs Unix Domain Socket for MySQL

I’m testing Percona Server for MySQL 8.0.19 running on Ubuntu 18.04 on a Dual Socket 28 Core/56 Threads Server.  (Though I have validated results on 4 …

Percona Server for MySQL 8.0.18 ships all functionality to run Group Replication and InnoDB Cluster setups, so I decided to evaluate how it works and how it compares with Percona XtraDB Cluster in some situations.

For this I planned to use three bare metal nodes, SSD drives, and a 10Gb network available for in-between nodes communication, but later I also added tests on three bare metal nodes with NVMe drives and 2x10Gb network cards.

To simplify deployment, I created simple ansible scripts.

Load Data

The first initial logical step is to load data into an empty cluster, so let’s do this with our sysbench-tpcc …

In my last blog post I showed you how to get the entire Percona “Stack” up and running on a Raspberry Pi. This time around, I would like to show the impact on performance between using an SSD hard disk and a standard hard disk.

Disk performance is a key factor in Percona Server for MySQL (or any RDB platform) performance on a Raspberry Pi 4.

Test set up

Each test below was run three times per Hard Disk and I took the best of the three for comparison.

Hardware

• Raspberry Pi 4+ with 4GB ram.
• Disk 1: USB3 Western Digital My Passport Ultra, 1TB
• Disk 2: USB3 KEXIN 240GB Portable External SSD Drive

Hardware stayed consistent …

Database administrators are responsible for maintaining the privacy and integrity of data. When the data contains confidential information, your company has a legal obligation to ensure that privacy is maintained. Even so, being able to access the information contained in that dataset, for example for testing or reporting purposes, has great value so what to do? MySQL Enterprise Edition offers data masking and de-identification, so I decided to contribute similar functionality to Percona Server for MySQL. In this post, I provide some background context and information on how to use these new functions in practice.

Some context

One of the most important assets of any company is data. Having good data allows engineers to build better …

Some say that the best password is the one you don’t have to remember. That’s possible with MySQL, thanks to the auth_socket plugin and its MariaDB version unix_socket.

Neither of these plugins is new, and some words have been written about the auth_socket on this blog before, for example: how to change passwords in MySQL 5.7 when using plugin: auth_socket. But while reviewing what’s new with MariaDB 10.4, I saw that the unix_socket now comes installed by default and is one of the authentication methods (one of them because in MariaDB 10.4 a single user can have more than one authentication plugin, …

ProxySQL 2.0.7, released by ProxySQL, is now available for download in the Percona Repository along with Percona’s proxysql-admin tool.

ProxySQL is a high-performance proxy, currently for MySQL and database servers in the MySQL ecosystem (like Percona Server for MySQL and MariaDB). It acts as an intermediary for client requests seeking resources from the database. René Cannaò created ProxySQL for DBAs as a means of solving complex replication topology issues.

This release includes ProxySQL 2.0.7 which introduces many new features and enhancements and also …

Percona announces the release of Percona Server for MySQL 5.7.27-30 on August 22, 2019 (downloads are available here and from the Percona Software Repositories). This release merges changes of MySQL 5.7.27, including all the bug fixes in it. Percona Server for MySQL 5.7.27-30 is now the current GA release in the 5.7 series. All of Percona’s software is open-source and free.

Bug Fixes:

• Parallel doublewrite buffer writes must crash the server on an I/O error occurs. Bug fixed …