vmstat(1)						      General Commands Manual							 vmstat(1)

NAME

       vmstat - Displays virtual memory statistics

SYNOPSIS

       vmstat interval [count]

       vmstat [-D  | -f  | -i  | -M  | -p  | -P  | -r rad_id | -R  | -s  | -w]

       The vmstat command displays system statistics for virtual memory, processes, trap, and CPU activity.

OPTIONS

       Displays  debugging  information  if  kmem_debug  is set.  Displays only statistics about the number of forks since system startup (see the
       fork() call).  Displays the following virtual memory statistics: # vmstat -i Virtual Memory Statistics: (pagesize = 8192)
	 procs	 memory        pages			       intr	  cpu
	 r  w  u act free wire fault  cow zero react  pin pout in  sy  cs us sy id
	 2 82 29 23K  12K 4906	  3M 963K 834K	 620 710K    0 73  30 391  0  2 98 Displays information  about	memory	usage  by  buckets.   This
       information  can be used for kernel debugging.  Displays statistics for the vm and ubc subsystems for all Resource Affinity Domains (RADs).
       Typical output (derived from a single-RAD, single-CPU server) is shown in the following example: # vmstat -p

       Total RADs: 1   Total CPUs: 1   Total Ticks: 512

	 36441297   VM faults			     1677   VM kfaults
	  2115850   VM cowcopy			     1677   VM kzfod
		0   VM pagesteal			0   VM prewrites
		0   VM anon_prewrites			0   VM swap_prewrites
		0   VM cleanrecs			0   VM swaprecs
		0   VM lmsteal				0   VM lmstealwins
		0   VM ffl				0   VM pout_scan
		0   VM pout_pagescan			0   VM pout_call
		0   VM pout				0   VM pout_target
		0   VM pout_burst		    12548   VM act_scans
	    12548   VM act_moves			0   VM lock_fails
		0   VM migrations
	  2547665   VM TOT cowfaults		  3813949   VM TOT zfod
		0   VM TOT iowrites			0   VM TOT pgwrites
	 26823910   VM TOT ioreads			0   VM TOT pgreads
	     1423   VM TOT reactivate
		0   UBC allocscans			0   UBC alloceol
		0   UBC allocpush			0   UBC allocstole
		0   UBC allocseq			0   UBC wacalls
		0   UBC wascans 			0   UBC waeol
		0   UBC prges				0   UBC prgscans
		0   UBC prgeol				0   UBC prgburst
		0   UBC prgfree 			0   UBC mmapfree
	    79566   UBC wdeny				0   UBC hardsteals
		0   UBC stealscans			0   UBC dirtywra
		0   UBC reclaim 			0   UBC pagesteal
	 42127497   UBC lookups 		 41985615   UBC lookuphits
		0   UBC ffl				0   UBC lmsteal
		0   UBC lmstealwins			0   UBC seqdrain
	   144957   UBC TOT alloc			0   UBC TOT iowrites
		0   UBC TOT reactivate			0   UBC TOT pgwrites

       Displays the following accumulated statistics about physical memory use: Sum of the total physical memory in the machine.   This  statistic
       describes  how physical memory is clustered.  It shows where memory is being used (pal, os, and nvram), the starting and ending pageframes,
       and the total amount of memory used.  This statistic shows a breakdown of physical memory used by the operating system (such as text, data,
       and bss).  It contains the starting and ending pageframes, memory usage per category, and total memory used.  This statistic provides snap-
       shot of where managed physical memory resides when the vmstat command was run.  It indicates the the number of pages in	the  free,  active
       and  inactive  queues, the number of wired pages, and the number of pages held in the unified buffer cache (UBC).  This statistic describes
       the physical pages that are wired in memory. The fields show the number of wired pages in anonymous(vm) memory, the  UBC,  pages  used  for
       meta  data,  the  kernel malloc pools, contiguous memory, and pages used for page table entries (ptes). The display typically shows: vm and
       ubc wired pages meta data, malloc, and contig pages user, kernel, and free ptepages.  Displays virtual memory statistics for the  specified
       Resource  Affinity Domain (RAD) only. The rad_id is an integer assigned automatically by the system. Typical output is shown in the follow-
       ing example, which has been reformatted for ease of reference: # vmstat -r 0 Virtual Memory Statistics: (pagesize = 8192)
	     procs	   memory				  pages
	RAD r	w  u st sw act actv actu acti free wire wirv wiru fault
	  0 2 157 27  0  0 31K 4928  18K 8813  24K 6544 3015	0   36M

				   intr       cpu
	 cow zero react  pin pout  in  sy  cs us sy id
	  2M   3M  1423  26M	0 102 249 229  0  1 99 Displays information for all Resource Affinity Domains  (RADs).	Typical  output  is  shown
       under  the  -r option.  Displays the following accumulated statistics along with the page size: Total number of pages that are currently in
       use but can be used for paging.	Total number of VM pages that are allocated but are most likely to be used for paging.	 Total	number	of
       unreferenced  (clean) pages that are available for use.	Total number of pages that are currently in use and cannot be used for paging (not
       a real list).  Number of address translation faults that have occurred.	Number of copy-on-write page faults, which occur if the  requested
       page  is  shared  by a parent process and one or more child processes (using the fork function) and if one of the processes needs to modify
       the page.  In this case, VM loads a new address into the translation buffer and copies the contents of the  requested  page  into  the  new
       address for modification by the process.  Number of zero-filled-on-demand page faults, which occur if VM cannot find the page in the inter-
       nal data structures and if the requested page is new and has never been referenced.  In this case, VM initializes a physical page (the con-
       tents  of the page are zeroed out) and loads the address into the page table.  Number of pages that have been faulted while on the inactive
       list.  Number of requests for pages from a pager.  Number of pages that have been paged out.  Number of task and thread	context  switches.
       Number  of nonclock device interrupts.  Number of system calls called.  Appends iowait information to the default output as follows:.  Vir-
       tual Memory Statistics: (pagesize = 8192)
	 procs	    memory	  pages 		intr	   cpu
	 r   w	 u  act free wire fault  cow  pin pout	in  sy	cs us sy id iowait
	 2  82	29  23K  12K 4905    3M 963K 710K    0	73  30 391  0  2 98	 0

DESCRIPTION

       The value of interval is a time in seconds, causing vmstat to display statistics at the specified interval.   The  first  report  generated
       includes  statistics  for  the  time since the last reboot. Each subsequent report is for the specified interval only. If you specify count
       after interval, it specifies the number of reports generated.  For example, vmstat 1 10 produces 10 reports  at	1-second  intervals.   You
       cannot specify count without interval, since the first numeric argument to vmstat is always assumed to be interval.

       At  any	time, system memory can be in use by the kernel in kseg, wired (pages that are currently in use and cannot be used for paging), on
       the active list (pages that are currently in use but can be used for paging), on the inactive list (pages that are allocated but  are  most
       likely  to  be  used for paging), on the free list (pages that are clean and available for use), or used by the Unified Buffer Cache (UBC).
       The vmstat command does not report on the memory in kseg and memory used by the UBC.

       The following values are displayed:

       Process information: Number of threads that are running or are runnable.  Number of threads waiting interruptibly.  Number of threads wait-
       ing uninterruptibly.

       Virtual memory information: Total number of pages on the active list, the inactive list (pages that are allocated but are most likely to be
       used for paging), and the Unified Buffer Cache (UBC) least recently used (LRU) list.  Total number of pages that are  clean  and  available
       for  use.   Total number of pages that are currently in use and cannot be used for paging (not a real list).  Number of address translation
       faults that have occurred.  Number of copy-on-write page faults, which occur if the requested page is shared by a parent process and one or
       more  child processes (using the fork function) and if one of the processes needs to modify the page.  In this case, VM loads a new address
       into the translation buffer and copies the contents of the requested page into the new address for modification by the process.	Number	of
       zero-filled-on-demand  page faults, which occur if VM cannot find the page in the internal data structures and if the requested page is new
       and has never been referenced.  In this case, VM initializes a physical page (the contents of the  page	are  zeroed  out)  and	loads  the
       address	into  the  page  table.   Number  of pages that have been faulted while on the inactive list.  Number of requests for pages from a
       pager.  Number of pages that have been paged out.

       Interrupt information: Number of nonclock device interrupts per second.	Number of system calls called per  second.   Number  of  task  and
       thread context switches per second.

       CPU information: Percentage of user time for normal and priority processes.  Percentage of system time.	Percentage of idle time.  Percent-
       age of iowait. If the -w option is not specified, the iowait time is included in the id statistic.

       Specify -f to display fork statistics only.  Specify -s for a single display of accumulated statistics, as well as page size.

SEE ALSO

       Commands:  iostat(1), sysman(8)

																	 vmstat(1)