4.3BSD - /usr/man/cat3/vtimes.0

VTIMES(3C)                                                          VTIMES(3C)


NAME
       vtimes - get information about resource utilization

SYNOPSIS
       #include <sys/vtimes.h>

       vtimes(par_vm, ch_vm)
       struct vtimes *par_vm, *ch_vm;

DESCRIPTION
       This facility is superseded by getrusage(2).

       Vtimes  returns  accounting information for the current process and for
       the terminated child processes of the current process.   Either  par_vm
       or  ch_vm  or both may be 0, in which case only the information for the
       pointers which are non-zero is returned.

       After the call, each buffer contains information as defined by the con‐
       tents of the include file /usr/include/sys/vtimes.h:

       struct vtimes {
            int  vm_utime;      /* user time (*HZ) */
            int  vm_stime;      /* system time (*HZ) */
            /* divide next two by utime+stime to get averages */
            unsigned vm_idsrss;      /* integral of d+s rss */
            unsigned vm_ixrss;       /* integral of text rss */
            int  vm_maxrss;          /* maximum rss */
            int  vm_majflt;          /* major page faults */
            int  vm_minflt;          /* minor page faults */
            int  vm_nswap;      /* number of swaps */
            int  vm_inblk;      /* block reads */
            int  vm_oublk;      /* block writes */
       };

       The  vm_utime and vm_stime fields give the user and system time respec‐
       tively in 60ths of a second (or 50ths if that is the frequency of  wall
       current  in  your  locality.)  The vm_idrss and vm_ixrss measure memory
       usage.  They are computed by integrating the number of memory pages  in
       use  each  over  cpu  time.   They are reported as though computed dis‐
       cretely, adding the current memory usage (in 512 byte pages) each  time
       the  clock ticks.  If a process used 5 core pages over 1 cpu-second for
       its data and stack, then vm_idsrss would have  the  value  5*60,  where
       vm_utime+vm_stime would be the 60.  Vm_idsrss integrates data and stack
       segment usage, while vm_ixrss integrates text segment usage.  Vm_maxrss
       reports the maximum instantaneous sum of the text+data+stack core-resi‐
       dent page count.

       The vm_majflt field gives the number of page faults which  resulted  in
       disk  activity;  the  vm_minflt  field  gives the number of page faults
       incurred in simulation of reference bits; vm_nswap  is  the  number  of
       swaps  which  occurred.   The number of file system input/output events
       are reported in vm_inblk and vm_oublk These numbers  account  only  for
       real i/o; data supplied by the caching mechanism is charged only to the
       first process to read or write the data.

SEE ALSO
       time(2), wait3(2), getrusage(2)


4th Berkeley Distribution        May 12, 1986                       VTIMES(3C)