Usage:
vmstat [options] [delay [count]]
Options:
-a, --active active/inactive memory 显示活跃和非活跃内存
-f, --forks number of forks since boot 显示从系统启动至今的fork数量
-m, --slabs slabinfo 显示slabinfo信息
-n, --one-header do not redisplay header 在周期性循环输出时，输出的头部信息仅显示一次
-s, --stats event counter statistics 显示内存相关统计信息及多种系统活动数量
-d, --disk disk statistics 显示磁盘相关统计信息
-D, --disk-sum summarize disk statistics 汇总硬盘相关统计信息
-p, --partition <dev> partition specific statistics 显示指定磁盘分区统计信息
-S, --unit <char> define display unit 使用指定单位显示。例如，k或K表示1000字节，m或M表示1000000字节
-w, --wide wide output 更宽的输出信息
-t, --timestamp show timestamp 显示时间列
-h, --help display this help and exit
-V, --version output version information and exit 显示vmstat的版本信息
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.
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
requested writes: Total number of write requests made for partition
FIELD DESCRIPTION FOR SLAB MODE
cache: Cache name
num: Number of currently active objects
total: Total number of available objects
size: Size of each object
pages: Number of pages with at least one active object
NOTES
vmstat does not require special permissions.
These reports are intended to help identify system bottlenecks. Linux vmstat does not count itself as a running process.
All linux blocks are currently 1024 bytes. Old kernels may report blocks as 512 bytes, 2048 bytes, or 4096 bytes.
Since procps 3.1.9, vmstat lets you choose units (k, K, m, M). Default is K (1024 bytes) in the default mode.
vmstat uses slabinfo 1.1
FILES
/proc/meminfo
/proc/stat
/proc/*/stat
SEE ALSO
free(1), iostat(1), mpstat(1), ps(1), sar(1), top(1)
BUGS
Does not tabulate the block io per device or count the number of system calls.
AUTHORS
Written by Henry Ware ⟨al172@yfn.ysu.edu⟩.
Fabian Frédérick ⟨ffrederick@users.sourceforge.net⟩ (diskstat, slab, partitions...)
REPORTING BUGS
Please send bug reports to ⟨procps@freelists.org⟩