Recently, we performed a database engine major version upgrade in one of our customers’ environments from MySQL 5.7.26 to 8.0.27. After this version upgrade, we experienced issues with backups and replication for one of the nodes.

In this article, I will explain these issues in detail and recommend a way to take backups from a replication environment.

To begin with, we upgraded all the database nodes from 5.7.26 to 8.0.27 and as a recommended way we have a backup set-up from one of the replica nodes. Physical backups are being taken using Percona XtraBackup (PXB) so it does not lock the database during the backup.

With MySQL 5.7, a backup was taken using PXB 2.4. Due to the new data dictionaries, redo log and undo log in MySQL 8.0, we also upgraded PXB to 8.0.27 to avoid …

Taking a MySQL backup using Percona XtraBackup (PXB) consists of basically two steps: 1) take the backup and 2) prepare the backup.

Briefly speaking, taking a backup means that PXB will copy all of the files from your instance and transfer them to another location. While it does the copy, it spawns a thread that will monitor the InnoDB redo log (WAL/transaction log) and store a copy of all the new redo log entries generated by the server during the backup.

Before restoring the backup into a new instance, users have to prepare the backup. This operation is the same as the crash recovery steps that the MySQL server does after a server crash.

It consists of reading all the redo log entries into memory, categorizing them by space id and page id, reading the relevant pages into memory, and checking the LSN number on the page and on …

Having a backup of your database is like insurance, you have to pay a monthly price to ensure you have a service available when you need to. When talking about backups, the storage required to keep your backups is what comes into factor when talking about price, the bigger your backup, or the bigger the retention period, the more it will cost.

Compressing your backups is a common practice to reduce this cost. Currently, Percona XtraBackup (PXB) has support for two compression algorithms: quicklz (which is an abandoned project and will soon be deprecated in PXB) and LZ4.

Today we are glad to introduce support for a new compression algorithm in Percona XtraBackup 8.0.30 – …

Oracle’s MySQL 8.0.29 release extended the support for ALTER TABLE … ALGORITHM=INSTANT to 1) allow users to instantly add columns in any position of the table, and 2) instantly drop columns. As part of this work, the InnoDB redo log format has changed for all DML operations on the server. This new redo log format introduced a design flaw that can cause data corruption for tables with INSTANT ADD/DROP COLUMNS.

The corruption happens when InnoDB crash recovery takes place. InnoDB applies redo logs at startup. Percona XtraBackup copies the redo log during backup and applies it as part of the –prepare step to bring the backup to a consistent state.

Percona fixed the corruption issue and several other issues with the INSTANT ADD/DROP column …

Earlier last week, Oracle released their Q2 releases series. Unlike previous releases, backward compatibility has now been broken with previous versions of MySQL.

MySQL 8.0.29 extended the support for the online DDL algorithm INSTANT. Prior to 8.0.29 only adding columns to the end of the table was supported.

In 8.0.29, this functionality was extended to allow the INSTANT algorithm the ability to add columns in any position of the table as well to drop columns. This new functionality required the redo log version to increase and new redo log types to be added, thus making it incompatible with older versions of the MySQL server and also older versions of Percona Xtrabackup. Please note that an in-place minor version downgrade of …

KMIP (Key Management Interoperability Protocol) is an open standard developed by OASIS (Organization for Advancement of Structured Information Standards) for the encryption of stored data and cryptographic key management.

Percona Server for MySQL 8.0.27 and Percona XtraBackup 8.0.27 now include a KMIP keyring plugin to enable the exchange of cryptographic keys between a key management server and the database for encryption purposes. The procedure to use them with HashiCorp Vault Enterprise is described below.

Install Hashicorp Vault Enterprise

We will first install Hashicorp Vault Enterprise on Ubuntu Linux “Bionic” and then enable …

A little bit ago, I released a blog post comparing the backup performance of different MySQL tools such as mysqldump, the MySQL Shell feature called Instance Dump, mysqlpump, mydumper, and Percona XtraBackup. You can find the first analysis here:

Backup Performance Comparison: mysqldump vs. MySQL Shell Utilities vs. mydumper vs. mysqlpump vs. XtraBackup …

Backups are a key part of a disaster recovery strategy, making sure you can continue or restore your business in case of an unwanted event with your data.

We always work on trying to improve Percona XtraBackup reliability, always favoring consistency, attempting to make unwanted outcomes be noticed as earlier as possible in the process.

Enabling –strict by Default

As of the upcoming release of 8.0.27, XtraBackup will no longer accept invalid parameters. Since the beginning of the times, validation of parameters has been a difficult task for XtraBackup as it mixes server-side and XtraBackup only parameters.

Starting at Percona XtraBackup 8.0.7 we implemented …

Don’t Try This at Home!

Disclaimer: The procedure described in this blog post is not officially supported by Percona XtraBackup. Use it under your responsibility. I tested and used it successfully, but your mileage may vary.

Note from the author: Wikipedia defines clickbait as text (or a link) that is designed to attract attention and to entice users to read that online content, with a defining characteristic of being deceptive. Maybe the headline of this post is a bit deceptive, as there is no Percona XtraBackup for Windows, but I hope you will not feel deceived after reading this blog post, I just felt that it was funny to use a clickbait-style while writing it.

He Couldn’t Believe it When He Read That Post!

Pep had to migrate a client database from Windows to Linux …

Chasing bugs can be a tedious task, and multi-threaded software doesn’t make it any easier. Threads will be scheduled at different times, instructions will not have deterministic results, and in order for one to reproduce a particular issue, it might require the exact same threads, doing the exact same work, at the exact same time. As you can imagine, this is not straightforward.

Let’s say your database is crashing or even having a transient stall.  By the time you get to it, the crash has happened and you are stuck restoring service quickly and doing after-the-fact forensics.  Wouldn’t it be nice to replay the work from right before or during the crash and see exactly what was happening?

Record and Replay is a technique where we record the execution of a program allowing it to be replayed over and over producing the same result. Engineers at …