As the world’s most popular open-source database, MySQL has been around the block more than a few times. Traditionally installed in on-premise data centers, recent years have shown a major trend for MySQL in the cloud, and near the top of this list is Amazon RDS.

Amazon RDS allows you to deploy scalable MySQL servers within minutes in a cost-efficient manner with easily resizable hardware capacity. This frees you up to focus on application development and leaves many of the traditional database administration tasks such as backups, patching, and monitoring in the hands of AWS.

In this post I’d like to go over six important benefits of Amazon RDS, and why a move into RDS may be the right move for you.

Easy Deployment

Amazon RDS allows you to use either the AWS Management Console or a set of APIs to create, delete, and modify your database instances. You have full control of access and security …

The innodb_io_capacity and innodb_io_capacity_max are often misunderstood InnoDB parameters. As consultants, we see, at least every month, people setting this variable based on the top IO write specifications of their storage. Is this a correct choice? Is it an optimal value for performance? What about the SSD/Flash wear leveling?

Innodb_io_capacity 101

Let’s begin with what the manual has to say about innodb_io_capacity:

“The innodb_io_capacity variable defines the number of I/O operations per second (IOPS) available to InnoDB background tasks, such as flushing pages from the buffer pool and merging data from the change buffer.“

What does this mean exactly? …

If you do a quick web search about UUIDs and MySQL, you’ll get a fair number of results. Here are just a few examples:

• Storing UUID and Generated Columns
• Storing UUID Values in MySQL
• Illustrating Primary Key models in InnoDB and their impact on disk usage
• MySQL UUID Smackdown: UUID vs. INT for Primary Key
• GUID/UUID Performance Breakthrough
• …

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, …

Starting with the experimental release of Percona XtraDB Cluster 8.0, we have made changes to the SST process to make the process more robust and easier to use.

• mysqldump and rsync are no longer supported SST methods.

  Support for mysqldump was deprecated starting with PXC 5.7 and has now been completely removed.

  MySQL 8.0 introduced a new Redo Log format that limited the use of rsync while upgrading from PXC 5.7 to 8.0. In addition, the new Galera-4 also introduced changes that further limits the use of rsync.

  The only supported SST method is xtrabackup-v2.

• A separate Percona XtraBackup installation is no longer required.

  The required …

The problem

In PXC 5.6 and 5.7, when using xtrabackup-v2 as the SST method, the DBA must create a user with the appropriate privileges for use by Percona XtraBackup (PXB). The username and password of this backup user are specified in the wsrep_sst_auth variable.

This is a problem because this username and password was being stored in plaintext and required that the configuration file be secured.

The PXC 8.0 solution

(This feature is still under development and may change before PXC 8.0 GA)

Because the wsrep_sst_auth is only needed on the donor side to take a backup, PXC 8.0 uses an internal user (created specifically for use by PXC) with a randomly generated password. Since this user is only needed on the donor, the plaintext password is not needed on the joiner …

Percona is happy to announce the first experimental binary of Percona XtraDB Cluster 8.0 on October 1, 2019. This is a major step for tuning Percona XtraDB Cluster to be more cloud- and user-friendly. This release combines the updated and feature-rich Galera 4, with substantial improvements made by our development team.

Improvements and New Features

Galera 4, included in Percona XtraDB Cluster 8.0, has many new features. Here is a list of the most essential improvements:

• Streaming replication supports large transactions
• The synchronization functions allow action coordination (wsrep_last_seen_gtid, wsrep_last_written_gtid, wsrep_sync_wait_upto_gtid)
• More granular and improved error logging. wsrep_debug is now a multi-valued variable to assist in controlling the logging, and logging messages have been significantly improved.
…

In a previous post, I showed you how to compile Percona Mysql 5.7 on Raspberry PI 3. Now, I’ll show you how to compile and run the latest version of Percona XtraDB Cluster 5.7.26.

We will need at least 3 RaspberryPi 3 boards, and I recommend you use an external SSD drive to compile and use as MySQL’s “datadir” to avoid the stalls associated with the microSD card, which will cause PXC to run slow.

In this post, we are going to run many OS commands and configure PXC. I recommend having minimal knowledge about PXC and Linux commands.

How to install CentOS

Download the centos image from this link …

If you have been around MySQL for any length of time, you are probably aware that choosing the correct data types and optimizing your schema are actually important tasks.  A few years back at Percona Live 2016, I gave an introductory talk on schema review and optimization. Here’s the video:

I was thinking about that talk in the context of some of my current clients.  Though I had worked on extremely large database deployments during my earlier tenure at Percona, it was often more of an outlier.  Now, working as a Technical Account Manager with our largest clients, it is much more common.

The Fundamental Problem

I’d like to expand my thoughts on the “choosing the smallest data type you can” principle from my 2016 slides through the lens of a few of my 2019 …

Percona is happy to announce the release of Percona XtraDB Cluster 5.7.27-31.39 on September 18, 2019. Binaries are available from the downloads section or from our software repositories.

Percona XtraDB Cluster 5.7.27-31.39 is now the current release, based on the following:

• Percona Server for MySQL 5.7.27-30
• Codership WSREP API release 5.7.27
• Codership Galera library 3.28

All Percona software is open-source and free.

Bugs Fixed

• PXC-2432: PXC was not …