Use a tiny, built-in tool to reveal CPU, memory and I/O pressure quickly. 16.11.2025 | reading time: 2 min vmstat gives a compact, immediate view of CPU, memory, swap and I/O activity from the command line, so he can spot pressure points without heavyweight tools. A live troubleshooting example Run a short sampling to see live behaviour; for example: `vmstat 1 5` and examine the per-second rows, for instance: ```procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----\n r b swpd free buff cache si so bi bo in cs us sy id wa\n 5 0 0 123456 23456 345678 0 0 1024 256 500 1000 10 5 80 5\n 2 0 0 120000 20000 340000 0 0 512 128 480 960 15 10 70 5\n```; if he sees sustained high "r" values the CPU is saturated, while rising "wa" means processes wait for disk I/O. What to watch first Focus on a few fields: "r" shows runnable processes (CPU demand), "b" blocked tasks, "si/so" indicate swapping activity, "bi/bo" show block I/O rates and the CPU columns "us/sy/id/wa" reveal user, system, idle and I/O wait time; also remember the first vmstat row shows averages since boot so always use an interval to get live samples. Deeper reads and flags Use `vmstat -s` for counters and events, `vmstat -d` for disk statistics and `vmstat -m` for slab info; change the interval and count to turn averages into time series and combine vmstat with simple scripts for lightweight logging. Complementary instruments vmstat is lightweight and excellent for a quick triage, but he will often follow up with `top` for per-process hotspots, `iostat` for fine-grained device throughput and `sar` for historical trends collected over time. Where to go next Start diagnosing with vmstat, then practice interpreting patterns on real systems; deepen skills by learning related tools and consider formal certification to validate knowledge with paths such as CompTIA Linux+ or LPIC-1 and focused exam preparation at bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. utilities processes troubleshooting storage
