NOTE
pidstat
Per-process and per-task CPU, memory, I/O, fault, and context-switch statistics.
This is a historical learning note and may contain outdated or incomplete understanding.
pidstat samples activity for individual processes and, with suitable options, threads/tasks. It can report CPU use, memory/page faults, I/O, and context-switch behavior over intervals.
It is useful after host-level tools show pressure and you need to identify which process contributes to it. Sample through the incident window and distinguish CPU consumption from waiting, I/O throughput from latency, and voluntary from involuntary context switches.