NAME    [Toc]    [Back]

     getrusage - get information about resource utilization

SYNOPSIS    [Toc]    [Back]

     #include <sys/time.h>
     #include <sys/resource.h>

     #define RUSAGE_SELF      0
     #define RUSAGE_CHILDREN  -1

     int
     getrusage(int who, struct rusage *rusage);

DESCRIPTION    [Toc]    [Back]

     getrusage() returns  information  describing  the  resources
utilized by the
     current process, or all its terminated child processes.  The
who parameter
 is either RUSAGE_SELF or RUSAGE_CHILDREN.  The buffer to
which rusage
     points will be filled in with the following structure:

     struct rusage {
             struct timeval ru_utime; /* user time used */
             struct timeval ru_stime; /* system time used */
             long ru_maxrss;          /* max resident set size */
             long ru_ixrss;            /*  integral  shared  text
memory size */
             long  ru_idrss;            /* integral unshared data
size */
             long ru_isrss;           /* integral unshared  stack
size */
             long ru_minflt;          /* page reclaims */
             long ru_majflt;          /* page faults */
             long ru_nswap;           /* swaps */
             long  ru_inblock;          /* block input operations
*/
             long ru_oublock;         /* block output  operations
*/
             long ru_msgsnd;          /* messages sent */
             long ru_msgrcv;          /* messages received */
             long ru_nsignals;        /* signals received */
             long   ru_nvcsw;             /*   voluntary  context
switches */
             long  ru_nivcsw;           /*  involuntary   context
switches */
     };

     The fields are interpreted as follows:

     ru_utime     the total amount of time spent executing in user mode.

     ru_stime     the total amount of time spent  in  the  system
executing on
                  behalf of the process(es).

     ru_maxrss     the  maximum  resident  set  size utilized (in
kilobytes).

     ru_ixrss     an integral value indicating the amount of memory used by
                  the  text  segment  that  was also shared among
other processes.
                  This value is expressed in units of kilobytes *
ticks-of-execution.


     ru_idrss      an  integral  value  of the amount of unshared
memory residing
                  in the data segment of a process (expressed  in
units of
                  kilobytes * ticks-of-execution).

     ru_isrss      an  integral  value  of the amount of unshared
memory residing
                  in the stack segment of a process (expressed in
units of
                  kilobytes * ticks-of-execution).

     ru_minflt     the number of page faults serviced without any
I/O activity;
                  here I/O activity is avoided  by  reclaiming  a
page frame from
                  the list of pages awaiting reallocation.

     ru_majflt     the  number  of  page faults serviced that required I/O activity.


     ru_nswap     the number of times a process was  swapped  out
of main memory.


     ru_inblock   the number of times the file system had to perform input.

     ru_oublock   the number of times the file system had to perform output.

     ru_msgsnd    the number of IPC messages sent.

     ru_msgrcv    the number of IPC messages received.

     ru_nsignals  the number of signals delivered.

     ru_nvcsw      the  number of times a context switch resulted
due to a process
 voluntarily giving up the processor before
its time
                  slice  was  completed  (usually to await availability of a resource).


     ru_nivcsw    the number of times a context  switch  resulted
due to a higher
  priority  process  becoming runnable or because the current
                  process exceeded its time slice.

NOTES    [Toc]    [Back]

     The numbers ru_inblock and ru_oublock 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.

ERRORS    [Toc]    [Back]

     getrusage() returns -1 on error.  The possible errors are:

     [EINVAL]      The who parameter is not a valid value.

     [EFAULT]      The address specified by the rusage  parameter
is not in a
                   valid part of the process address space.

SEE ALSO    [Toc]    [Back]

     gettimeofday(2), wait(2)

HISTORY    [Toc]    [Back]

     The getrusage() function call appeared in 4.2BSD.

BUGS    [Toc]    [Back]

     There  is no way to obtain information about a child process
that has not
     yet terminated.

OpenBSD      3.6                           June      4,      1993