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

　　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.

　　FIELD DESCRIPTION FOR DISK MODE

　　Reads

　　total: Total reads completed successfully

　　merged: grouped reads (resulting in one I/O)

　　sectors: Sectors read successfully

　　ms: milliseconds spent reading

　　Writes

　　total: Total writes completed successfully

　　merged: grouped writes (resulting in one I/O)

　　sectors: Sectors written successfully

　　ms: milliseconds spent writing

　　IO

　　cur: I/O in progress

　　s: seconds spent for I/O

　　FIELD DESCRIPTION FOR DISK PARTITION MODE

　　reads: Total number of reads issued to this partition

　　read sectors: Total read sectors for partition

　　writes : Total number of writes issued to this partition