Here’s a useful tool for quickly testing whether a disk (or a cloud block store volume) is a good candidate for your database WAL/redo logs and any other files that require low latency writes. The pg_test_fsync tool is bundled with standard Postgres packages, so no extra installation is needed. You don’t actually have to use Postgres as your database, this tool’s output is universally valuable for any workload requiring fast writes. - Linux, Oracle, SQL performance tuning and troubleshooting - consulting & training.