The Percona Database Performance Blog

Tuning Percona ClusterSync for MongoDB Performance

Percona ClusterSync for MongoDB (PCSM) synchronizes data from a source MongoDB cluster (including Atlas) to a target MongoDB cluster in two stages. It...

Percona ClusterSync for MongoDB Goes Highly Available: Active-Standby Failover

Editor’s Note: This article was originally authored by Inel Pandzic. Migrating data between MongoDB clusters is rarely a five-minute job. A larg...

Valkey Memory Optimization, Version by Version and Encoding: How Many Bytes Did Each Release Actually Save?

Introduction This RAM/Memory reduction is most useful for Valkey 9.1 environments that are key string heavy. They are used extensively in caching, ses...

PgQ and PgQue: Workflow Engines you might need in PostgreSQL

In many real production databases, we often see some tables receiving high-frequency updates (millions per day) and autovacuum running repeatedly (hun...

When pt-online-schema-change “where” Meets Galera: Understanding Chunk Auto-Resize and Flow Control

Percona Toolkit’s pt-online-schema-change (pt-osc) has long been the preferred solution for performing online schema changes with minimal downti...

DISTANCE() and VECTOR_DISTANCE(): Vector Similarity in Percona Server for MySQL 9.7

TL;DR Percona Server for MySQL 9.7.2-2 now supports DISTANCE() for vector similarity scoring directly in SQL (COSINE, EUCLIDEAN, MANHATTAN, DOT metric...

Evaluating LLM models for DBA tasks

  Evaluating LLM Models for DBA Tasks Large language models are increasingly capable of performing practical systems-administration tasks. I want...

Group Replication Beyond a Single Cluster: DC-DR with Percona (PS MySQL) Operator

A while ago, we discussed the cross-site replication feature of the Percona PXC operator. Recently, a similar cross-site replication feature was intro...

Too many GCache Page Files in MySQL Data Directory

Learn why PXC accumulates thousands of gcache.page.* files, how frozen GCache purging causes disk growth, and how to safely recover and rejoin using I...

pgBackRest Compression: How Much CPU Is a Smaller Backup Worth?

In this blog post, we’ll compare pgBackRest’s compression algorithms and levels to find where spending more CPU stops buying a meaningfull...