Hack 97. vmstat Command Examples

    For a typical performance monitoring all you need is only vmstat command. This display memory, swap, IO, system and cpu performance information.The following command executes vmstat every 1 second for 100 times.

    • b field: Total number of blocked process

    Memory section

    • Swpd field: Used swap space
    • Free field: Available free RAM
    • Buff field: RAM used for buffers
    • Cache field: RAM used for filesystem cache
    • Si field: Amount of memory swapped from disk per second

    IO Section

    • Bi field: Blocks received from disk
    • Bo field: Blocks sent to disk.
    • In field: Number of interrupts per second.
    • Cs field: Number of context switches per second.

    CPU Section

    • Us field: Time spend running user code. (non-kernel code)
    • Sy field: Time spent running kernel code.
    • Wa field: Time spent waiting for the IO