linux 监测命令(vmstat),功能为:显示虚拟内存信息。
命令格式:
[root@ztws ~]# vmstat -v
vmstat: invalid option -- 'v'
Usage:
vmstat [options] [delay [count]]
Options:
-a, --active active/inactive memory
-f, --forks number of forks since boot
-m, --slabs slabinfo
-n, --one-header do not redisplay header
-s, --stats event counter statistics
-d, --disk disk statistics
-D, --disk-sum summarize disk statistics
-p, --partition <dev> partition specific statistics
-S, --unit <char> define display unit
-w, --wide wide output
-t, --timestamp show timestamp
-h, --help display this help and exit
-V, --version output version information and exit
For more details see vmstat(8).
[root@ztws ~]# vmstat
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
r b swpd free buff cache si so bi bo in cs us sy id wa st
1 0 82696 125120 0 5858864 0 0 0 1 1 0 1 0 99 0 0
结果说明:
FIELD DESCRIPTION FOR VM MODE
Procs
r: The number of runnable processes (running or 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, included in idle.
st: Time stolen from a virtual machine. Prior to Linux 2.6.11, unknown.