Welcome back to my PostgreSQL optimization series! In previous posts, I covered installing PostgreSQL 18 with an optimized disk layout and relocating WAL files to a dedicated disk. Today, I'm tackling another critical performance optimization: moving temporary files to their own disk volume. If you've ever run complex queries involving large sorts or joins and watched your database slow to a crawl, this optimization is for you. Understanding PostgreSQL Temporary Files Before we dive into the how, let's understand the what and why. PostgreSQL creates temporary files when performing operations that exceed available memory. These files support operations like: Large sorts - When ORDER BY clauses process more data than fits in work_mem Hash joins - When joining large tables that exceed hash_mem limits Aggregations - GROUP BY operations on massive datasets Window functions - Complex analytical queries with partitioning Here's what makes temporary files unique:...
Moving PostgreSQL WAL Files to a Dedicated Disk: A Complete Guide In my previous post, I covered installing PostgreSQL 18 with a performance-optimized disk layout. Today, I'm diving deeper into one of the most impactful optimizations you can make: relocating your Write-Ahead Log (WAL) files to a dedicated disk volume. This seemingly simple change can dramatically reduce I/O contention and boost your database performance, especially for write-heavy workloads. Let me show you exactly how to do it safely. What Are WAL Files and Why Do They Matter? Write-Ahead Logs are the backbone of PostgreSQL's durability guarantees. They're sequential transaction logs that record every change made to your database before those changes hit the actual data files. Think of them as a detailed journal of everything happening in your database. WAL files serve two critical purposes: Crash Recovery : If PostgreSQL crashes unexpectedly, WAL files allow the database to replay transactions an...