How to Benchmark Linux Server Disk I/O with FIO

Linux Server Admin with Fexingo: Sysadmin, Bash, and Server Engineering · Jun 7, 2026 · 10m · transcript

Episode 36 of Linux Server Admin with Fexingo dives into disk I/O benchmarking with FIO. Lucas and Luna walk through a real-world scenario: a database server showing intermittent slow queries, traced to unexpected I/O latency. They explain how to install FIO, construct a basic random-read/write test, interpret the output (IOPS, latency percentiles, bandwidth), and compare against expected performance for SSDs and HDDs. The episode covers why default test parameters can mislead, how to match workloads (e.g., 4K random vs. 64K sequential), and a simple three-run methodology for reliable…