Virtual Memory Statistics ( vmstat ) 是报告关于进程,虚拟内存,磁盘,CPU活动的一个统计报告.
在一个多CPU系统中,vmstat统计所有个数的CPU的平均输出.为每个进程进行统计.没有参数时,vmstat显示每一行是自从系统启动以后的虚拟内存的活动情况.
vmstat 的语法我们可以通过linux的man 命令来查看。
将man 的结果导入到指定的文本
# man vmstat|col -b > /u01/tianlesoftware.txt
查看vmstat 用法
# man vmstat
VMSTAT(8) Linux Administrator’s Manual VMSTAT(8)
NAME
vmstat - Report virtual memory statistics
SYNOPSIS
vmstat [-a] [-n] [delay [ count]]
vmstat [-f] [-s] [-m]
vmstat [-S unit]
vmstat [-d]
vmstat [-p disk partition]
vmstat [-V]
DESCRIPTION
vmstat reports information about processes, memory, paging, block IO,
traps, and cpu activity.
The first report produced gives averages since the last reboot. Addi-
tional reports give information on a sampling period of length delay.
The process and memory reports are instantaneous in either case.
Options
The -a switch displays active/inactive memory, given a 2.5.41 kernel
or better.
The -f switch displays the number of forks since boot. This includes
the fork, vfork, and clone system calls, and is equivalent to the
total number of tasks created. Each process is represented by one or
more tasks, depending on thread usage. This display does not repeat.
The -m displays slabinfo.
The -n switch causes the header to be displayed only once rather than
periodically.
The -s switch displays a table of various event counters and memory
statistics. This display does not repeat.
delay is the delay between updates in seconds. If no delay is speci-
fied, only one report is printed with the average values since boot.
count is the number of updates. If no count is specified and delay is
defined, count defaults to infinity.
The -d reports disk statistics (2.5.70 or above required)
The -p followed by some partition name for detailed statistics (2.5.70
or above required)
The -S followed by k or K or m or M switches outputs between 1000,
1024, 1000000, or 1048576 bytes
The -V switch results in displaying version information.
FIELD DESCRIPTION FOR VM MODE
Procs
r: The number of processes waiting for run time.
b: The number of processes in uninterruptible sleep.
Memory