vmstat - Unix, Linux Command

The first report produced gives averages since the last reboot.  Additional
reports give information on a sampling period of length delay.
The process and memory reports are instantaneous in either case.




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 specified,
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.



r: The number of processes waiting for run time. 
b: The number of processes in uninterruptible sleep.



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)



si: Amount of memory swapped in from disk (/s).
so: Amount of memory swapped to disk (/s).



bi: Blocks received from a block device (blocks/s).
bo: Blocks sent to a block device (blocks/s).



in: The number of interrupts per second, including the clock.
cs: The number of context switches per second.





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.







total: Total reads completed successfully
merged: grouped reads (resulting in one I/O)
sectors: Sectors read successfully
ms: milliseconds spent reading



total: Total writes completed successfully
merged: grouped writes (resulting in one I/O)
sectors: Sectors written successfully
ms: milliseconds spent writing



cur: I/O in progress
s: seconds spent for I/O





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








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
totpages: Total number of allocated pages
pslab: Number of pages per slab




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    FIXME

/proc/meminfo
/proc/stat
/proc/*/stat





Written by Henry Ware <al172@yfn.ysu.edu>.
Fabian Fr\(&#146;ed\(&#146;erick <ffrederick@users.sourceforge.net> (diskstat, slab, partitions...)


Advertisements


    129 Lectures 
     23 hours 

 Eduonix Learning Solutions

    5 Lectures 
     4.5 hours 

 Frahaan Hussain

    35 Lectures 
     2 hours 

 Pradeep D

    41 Lectures 
     2.5 hours 

 Musab Zayadneh

    46 Lectures 
     4 hours 

 GUHARAJANM

    6 Lectures 
     4 hours 

 Uplatz
 Print
 Add Notes
 Bookmark this page