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Percona Distribution for MySQL 8.4.4 using Percona XtraDB Cluster (2025-04-16)

Percona Distribution for MySQL is more than just a version of MySQL; it is a comprehensive solution that combines Percona Server for MySQL with additional tools to create a cohesive environment. This distribution is reliable, scalable, and secure, ensuring that all components have been tested to work seamlessly together. You can choose from two download options: one that uses Percona Server for MySQL and another that utilizes Percona XtraDB Cluster. Refer to Install Percona Distribution for MySQL.

This release is based on Percona XtraDB Cluster 8.4.4-4.

Release highlights

Percona XtraDB Cluster 8.4.4-4

Implements the Clone plugin for State Snapshot Transfer (SST) Method. The Clone SST is a modern and efficient method that leverages MySQL’s native cloning capabilities to transfer data from a donor node to a Joiner node. It is faster and more resource-efficient compared to traditional methods like xtrabackup or rsync.

Percona Server for MySQL 8.4.4-4

Improves the Data masking performance by introducing an internal term cache. The new cache speeds up lookups for gen_blocklist() and gen_dictionary() functions by storing dictionary data in memory. However, if the dictionary table is modified directly (outside of the proper functions), the cache may become out of sync. To fix this, use the new masking_dictionaries_flush() function.

Changes also affect row-based replication: dictionary changes on the source server are replicated, but the term cache on the replica doesn’t update immediately. To address this, a new system setting, component_masking_functions.dictionaries_flush_interval_seconds(), can be set to automatically refresh the cache at specified intervals, helping replicas stay in sync.

Find more detailed information in the Data masking overview and in the Data masking component functions.

MySQL 8.4.4

Improvements and bug fixes introduced by Oracle for MySQL 8.4.4 and included in Percona Server for MySQL are the following:

  • Fixed an assertion in debug builds where certain IO buffer serializations caused system hangs. (Bug #37139618)

  • Resolved a failure when dropping the primary key and adding a new AUTO_INCREMENT column as the primary key in descending order using the INPLACE algorithm resulted in failure. (Bug #36658450)

  • Fixed incorrect results, including missing rows, in queries that used a descending primary key with the index_merge optimization. (Bug #106207, Bug #33767814)

  • Addressed a replication channel issue where MySQL failed to stop the channel properly when large transactions were being processed, and STOP REPLICA was requested. This issue also prevented graceful server shutdown, requiring process termination or system restart. (Bug #115966, Bug #37008345)

Find the complete list of bug fixes and changes in the MySQL 8.4.4 release notes.

Supplied components

Review each component’s release notes for What’s new, improvements, or bug fixes. The following is a list of the components supplied with the Percona XtraDB Cluster-based variation of the Percona Distribution for MySQL:

Component Version Description
Percona XtraBackup 8.4.0-2 An open-source hot backup utility for MySQL-based servers that doesn’t lock your database during the backup.
HAProxy 2.8.14 A high-availability and load-balancing solution for Percona XtraDB Cluster. This is a default proxy.
ProxySQL 2.7.1-1 A high performance, high-availability, protocol-aware proxy for MySQL.
Percona Toolkit 3.7.0 The set of scripts to simplify and optimize database operation.
replication_manager.sh 1.0 A tool to manage multi-source replication between multiple Percona XtraDB Cluster clusters.