Locking Concurrency on Netdata

Using FOR UPDATE SKIP LOCKED For Queue Workflows

Fri, 29 Aug 2025 00:00:00 +0000

One of the most common and powerful patterns in modern application development is the job queue. Whether you’re sending emails, processing images, or running complex calculations, offloading tasks to background workers is essential for building responsive and scalable systems. Many developers reach for dedicated queueing software like RabbitMQ or Redis, but for many use cases, your primary PostgreSQL database already has all the tools you need to build a robust, transactional, and incredibly performant job_queue_postgres.

How Autovacuum Causes PostgreSQL Deadlocks

Tue, 26 Aug 2025 00:00:00 +0000

You’ve meticulously optimized your application queries. Your transaction logic is sound. Yet, under heavy load, your system seizes up, logging the dreaded “deadlock detected” error. You dig into the logs, expecting to find two application transactions locked in a deadly embrace, but instead, you find a surprising culprit: one of the participants is the PostgreSQL autovacuum process. How can a routine maintenance task, designed to keep the database healthy, be the cause of a production-stopping postgres_deadlock?

Real-World PostgreSQL Deadlock Examples & Fixes

Mon, 25 Aug 2025 00:00:00 +0000

It’s 3 AM. The pager screams. Your application is throwing a cascade of errors, and users are reporting that the system is completely frozen. You dive into the logs and see the same ominous message repeating over and over: ERROR: deadlock detected. A PostgreSQL deadlock is one of the most abrupt and disruptive failures a database can experience. It’s not a performance degradation; it’s a hard stop where two or more transactions are locked in a fatal embrace, each waiting for a resource the other holds.

Early Deadlock Detection With pg_stat_kcache & eBPF

Sat, 09 Aug 2025 00:00:00 +0000

The dreaded deadlock. For anyone managing a high-traffic PostgreSQL database, it’s a familiar nemesis. The database logs a “deadlock detected” message, a transaction is unceremoniously aborted, and your application has to handle the fallout. This reactive cycle is frustrating; by the time you’re alerted, the damage is already done. Traditional postgres_metrics and monitoring tools are excellent at telling you that a deadlock occurred, but they fall short of explaining the subtle conditions that led to it.

What Is Database Concurrency? Problems & Control Techniques

Sun, 04 May 2025 00:00:00 +0000

Imagine trying to book the very last seat on a popular flight online. At the exact same moment, another person clicks “confirm” for the same seat. How does the system ensure only one booking goes through and the database remains accurate? This scenario highlights the core challenge of database concurrency.

In today’s world, almost every application interacts with databases accessed by multiple users or processes simultaneously. Database concurrency is the ability of a Database Management System (DBMS) to handle these simultaneous operations efficiently while maintaining data integrity and consistency. For developers, DevOps engineers, and SREs, understanding concurrency is vital for building reliable and performant applications. Let’s explore what concurrency entails, the problems it can cause if unmanaged, and the techniques used to control it.

MySQL ERROR 1205: Lock wait timeout exceeded; try restarting transaction