linux系统命令 vmstat

经常使用vmstat来查看系统的运行状况，实际上却还是有些细节被我忽略了！
今天正好兴起，就一次性弄清楚!
Procs
r: The number of processes waiting for run time.
b: The number of processes in uninterruptible sleep.
我们经常会看见r的数值比较大,也很明显的知道等待运行的进程比较多,
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)
内存使用情况的说明,和free显示的内容是一样的
Swap
si: Amount of memory swapped in from disk (/s).
so: Amount of memory swapped to disk (/s).
交换区的使用情况
IO
bi: Blocks received from a block device (blocks/s).
bo: Blocks sent to a block device (blocks/s).
对物理块的读写速率
System
in: The number of interrupts per second, including the clock.
cs: The number of context switches per second
in是中断次数/秒,cs是做上下文交换的次数/秒
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.
cpu的使用率,id为空闲cpu,wa为等待磁盘io的使用率!wa过高的话,说明磁盘io存在一定的瓶颈.
发现以前学的操作系统好像在这里找到了些影子.