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VTIMES(3)                   BSD Programmer's Manual                  VTIMES(3)

NAME
     vtimes - get information about resource utilization

SYNOPSIS
     #include <&lt;sys/vtimes.h>&gt;

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

DESCRIPTION
     This interface is obsoleted by getrusage(2).  It is available from the
     compatibility library, libcompat.

     The vtimes() function returns accounting information for the current pro-
     cess and for the terminated child processes of the current process.  Ei-
     ther 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 us-
     age.  They are computed by integrating the number of memory pages in use
     each over CPU time.  They are reported as though computed discretely,
     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.  The Vm_idsrss argument integrates data and stack seg-
     ment usage, while vm_ixrss integrates text segment usage.  The Vm_maxrss
     function reports the maximum instantaneous sum of the text+data+stack
     core-resident 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 in-
     curred in simulation of reference bits; vm_nswap is the number of swaps
     which occurred.  The number of file system input/output events are re-
     ported 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 pro-
     cess to read or write the data.

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

HISTORY
     The vlimit() function appeared in 4.2BSD.

4th Berkeley Distribution        June 4, 1993                                1