vmstat

vmstat

vmstat 可用來紀錄 processes, memory, paging, block IO, traps, 與 cpu activity。

例如

$ vmstat 1 # 1 是更新速度，單位為秒
procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
 r b swpd free buff cache si so bi bo in cs us sy id wa
 1 0 549368 13316 102388 91992 12 6 9 8 2 12 72 3 25 0
 2 0 549368 13316 102388 91992 0 0 0 0 156 1516 98 2 0 0
 2 0 549368 13312 102388 91992 0 0 0 0 125 534 99 1 0 0

....

 Procs
 r: The number of processes waiting for run time.
 b: The number of processes in uninterruptible sleep.

Memory
 swpd: the amount of virtual memory used.
 free: the amount of idle memory.
 buff: the amount of memory used as buffers.
 cache: the amount of memory used as cache.
 inact: the amount of inactive memory. (-a option)
 active: the amount of active memory. (-a option)

Swap
 si: Amount of memory swapped in from disk (/s).
 so: Amount of memory swapped to disk (/s).

IO
 bi: Blocks received from a block device (blocks/s).
 bo: Blocks sent to a block device (blocks/s).
 System
 in: The number of interrupts per second, including the clock.
 cs: The number of context switches per second.

CPU
 These are percentages of total CPU time.
 us: Time spent running non-kernel code. (user time, including nice time)
 sy: Time spent running kernel code. (system time)
 id: Time spent idle. Prior to Linux 2.5.41, this includes IO-wait time.
 wa: Time spent waiting for IO. Prior to Linux 2.5.41, shown as zero.