OSF

NAME

vmstat − Shows Mach virtual memory statistics

SYNOPSIS

vmstat interval [count]

vmstat [−f | −s]

The vmstat command displays statistics kept about virtual memory, processes, trap, and CPU activity. 

DESCRIPTION

If you specify interval, vmstat displays the statistics listed below every interval seconds. The first report is for all time since a reboot, and each subsequent report is for the last interval only. If you specifty count after interval, count specifies the number of reports. 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. 

The following values are displayed:

Process information:

rNumber of threads. 

wNumber of threads waiting interruptibly. 

uNumber of threads waiting uninterruptibly. 

Virtual memory information:

actTotal number of pages currently in use and pageable. 

freeTotal number of free pages in the system. 

wireTotal number of pages wired down. 

faultNumber of address translation faults that have occurred. 

cowNumber of copy on write page faults. 

zeroNumber of zero fill page faults. 

reactNumber of pages that have been faulted while on the inactive list. 

pinNumber of requests for pages from a pager. 

poutNumber of pages that have been paged out. 

Interrupt information:

inNumber of nonclock device interupts per second. 

syNumber of system calls called per second. 

csNumber of task and thread context switches per second. 

CPU information:

usPercentage of user time for normal and priority processes. 

syPercentage of system time. 

idPercentage of idle time. 

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

FLAGS

−fDisplays only statistics about the number of forks since system startup (see the fork() call). 

−sDisplays accumulated statistics along with the page size. 

RELATED INFORMATION

Commands: iostat(1). 

Functions: table(2).