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vmstat(1) [bsd man page]

VMSTAT(1)						      General Commands Manual							 VMSTAT(1)

NAME
vmstat - report virtual memory statistics SYNOPSIS
vmstat [ -fsi ] [ drives ] [ interval [ count ] ] DESCRIPTION
Vmstat delves into the system and normally reports certain statistics kept about process, virtual memory, disk, trap and cpu activity. If given a -f argument, it instead reports on the number of forks and vforks since system startup and the number of pages of virtual memory involved in each kind of fork. If given a -s argument, it instead prints the contents of the sum structure, giving the total number of several kinds of paging related events which have occurred since boot. If given a -i argument, it instead reports on the number of inter- rupts taken by each device since system startup. If none of these options are given, vmstat will report in the first line a summary of the virtual memory activity since the system has been booted. If interval is specified, then successive lines are summaries over the last interval seconds. ``vmstat 5'' will print what the system is doing every five seconds; this is a good choice of printing interval since this is how often some of the statistics are sampled in the system; others vary every second, running the output for a while will make it apparent which are recomputed every second. If a count is given, the statistics are repeated count times. The format fields are: Procs: information about numbers of processes in various states. r in run queue b blocked for resources (i/o, paging, etc.) w runnable or short sleeper (< 20 secs) but swapped Memory: information about the usage of virtual and real memory. Virtual pages are considered active if they belong to processes which are running or have run in the last 20 seconds. A ``page'' here is 1024 bytes. avm active virtual pages fre size of the free list Page: information about page faults and paging activity. These are averaged each five seconds, and given in units per second. re page reclaims (simulating reference bits) at pages attached (found in free list) pi pages paged in po pages paged out fr pages freed per second de anticipated short term memory shortfall sr pages scanned by clock algorithm, per-second up/hp/rk/ra: Disk operations per second (this field is system dependent). Typically paging will be split across several of the available drives. The number under each of these is the unit number. Faults: trap/interrupt rate averages per second over last 5 seconds. in (non clock) device interrupts per second sy system calls per second cs cpu context switch rate (switches/sec) Cpu: breakdown of percentage usage of CPU time us user time for normal and low priority processes sy system time id cpu idle If more than 4 disk drives are configured in the system, vmstat displays only the first 4 drives, with priority given to Massbus disk drives (i.e. if both Unibus and Massbus drives are present and the total number of drives exceeds 4, then some number of Unibus drives will not be displayed in favor of the Massbus drives). To force vmstat to display specific drives, their names may be supplied on the command line. FILES
/dev/kmem, /vmunix SEE ALSO
systat(1), iostat(1) The sections starting with ``Interpreting system activity'' in Installing and Operating 4.2bsd. 4th Berkeley Distribution March 15, 1986 VMSTAT(1)

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vmstat(1)						      General Commands Manual							 vmstat(1)

Name
       vmstat - report virtual memory statistics

Syntax
       vmstat [ interval [ count ] ]
       vmstat -v [ interval [ count ] ]
       vmstat -fKSsz
       vmstat -Kks namelist [ corefile ]

Description
       The command reports statistics on processes, virtual memory, disk, trap, and cpu activity.

       If  is  specified without arguments, this command summarizes the virtual memory activity since the system was last booted.  If the interval
       argument is specified, then successive lines are summaries of activity over the last interval seconds.  Because many statistics are sampled
       in  the system every five seconds, five is a good specification for interval; other statistics vary every second.  If the count argument is
       provided, the statistics are repeated count times.

       When you run the format fields are as follows:

       Procs: information about numbers of processes in various states.

	    r	 in run queue

	    b	 blocked for resources (i/o, paging, and so on.)

	    w	 runnable or short sleeper (< 20 seconds) but swapped

       faults:	trap/interrupt rate averages per second over the last 5 seconds.

	    in	 (non clock) device interrupts per second

	    sy	 system calls per second

	    cs	 cpu context switch rate (switches/second)

       cpu:  breakdown of percentage usage of cpu time

	    us	 user time for normal and low priority processes

	    sy	 system time

	    id	 cpu idle time

       Memory:	information about the use of virtual and real memory.  Virtual pages are considered active if they belong to processes	which  are
       running or have run in the last 20 seconds.

	    avm  active virtual pages

	    fre  size of the free list

       Pages are reported in units of 1024 bytes.

       If  the number of pages exceeds 9999, it is shown in a scaled representation.  The suffix k indicates multiplication by 1000 and the suffix
       m indicates multiplication by 1000000.  For example, the value 12345 appears as 12k.

       page: information about page faults and paging activity.  These are averaged every five seconds, and given in units per second.	 The  size
       of a unit is always 1024 bytes and is independent of the actual page size on a machine.

	    re	 page reclaims (simulating reference bits)

	    at	 pages attached (found in free list not swapdev or filesystem)

	    pi	 pages paged in

	    po	 pages paged out

	    fr	 pages freed per second

	    de	 anticipated short term memory shortfall

	    sr	 pages scanned by clock algorithm, per-second

       disk:   s0,  s1 ...sn: Paging/swapping disk sector transfers per second (this field is system dependent).  Typically paging is split across
       several of the available drives.  This will print for each paging/swapping device configured into the kernel.

Options
       -f     Provides reports on the number of forks and vforks since system startup and the number of pages of virtual memory involved  in  each
	      kind of fork.

       -K     Displays usage statistics of the kernel memory allocator.

       -k     Allows  a  dump  to be interrogated to print the contents of the sum structure when specified with a namelist and corefile.  This is
	      the default.

       -S     Replaces the page reclaim (re) and pages attached (at) fields with processes swapped in (si) and processes swapped out (so).

       -s     Prints the contents of the sum structure, giving the total number of several kinds of paging related events that have occurred since
	      boot.

       -v     Prints an expanded form of the virtual memory statistics.

       -z     Zeroes out the sum structure if the UID indicates root privilege.

Examples
       The following command prints what the system is doing every five seconds:
       vmstat 5
       To find the status after a core dump use the following:
       cd /usr/adm/crash
       vmstat -k vmunix.? vmcore.?

Files
       Kernel memory

       System namelist

																	 vmstat(1)
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