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Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd May 1, 2010 29.Dt GETRUSAGE 2 30.Os 31.Sh NAME 32.Nm getrusage 33.Nd get information about resource utilization 34.Sh LIBRARY 35.Lb libc 36.Sh SYNOPSIS 37.In sys/types.h 38.In sys/time.h 39.In sys/resource.h 40.Fd "#define RUSAGE_SELF 0" 41.Fd "#define RUSAGE_CHILDREN -1" 42.Fd "#define RUSAGE_THREAD 1" 43.Ft int 44.Fn getrusage "int who" "struct rusage *rusage" 45.Sh DESCRIPTION 46The 47.Fn getrusage 48system call 49returns information describing the resources utilized by the current 50thread, the current process, or all its terminated child processes. 51The 52.Fa who 53argument is either 54.Dv RUSAGE_THREAD , 55.Dv RUSAGE_SELF , 56or 57.Dv RUSAGE_CHILDREN . 58The buffer to which 59.Fa rusage 60points will be filled in with 61the following structure: 62.Bd -literal 63struct rusage { 64 struct timeval ru_utime; /* user time used */ 65 struct timeval ru_stime; /* system time used */ 66 long ru_maxrss; /* max resident set size */ 67 long ru_ixrss; /* integral shared text memory size */ 68 long ru_idrss; /* integral unshared data size */ 69 long ru_isrss; /* integral unshared stack size */ 70 long ru_minflt; /* page reclaims */ 71 long ru_majflt; /* page faults */ 72 long ru_nswap; /* swaps */ 73 long ru_inblock; /* block input operations */ 74 long ru_oublock; /* block output operations */ 75 long ru_msgsnd; /* messages sent */ 76 long ru_msgrcv; /* messages received */ 77 long ru_nsignals; /* signals received */ 78 long ru_nvcsw; /* voluntary context switches */ 79 long ru_nivcsw; /* involuntary context switches */ 80}; 81.Ed 82.Pp 83The fields are interpreted as follows: 84.Bl -tag -width ru_minfltaa 85.It Fa ru_utime 86the total amount of time spent executing in user mode. 87.It Fa ru_stime 88the total amount of time spent in the system executing on behalf 89of the process(es). 90.It Fa ru_maxrss 91the maximum resident set size utilized (in kilobytes). 92.It Fa ru_ixrss 93an 94.Dq integral 95value indicating the amount of memory used 96by the text segment 97that was also shared among other processes. 98This value is expressed 99in units of kilobytes * ticks-of-execution. 100Ticks are statistics clock ticks. 101The statistics clock has a frequency of 102.Fn sysconf _SC_CLK_TCK 103ticks per second. 104.It Fa ru_idrss 105an integral value of the amount of unshared memory residing in the 106data segment of a process (expressed in units of 107kilobytes * ticks-of-execution). 108.It Fa ru_isrss 109an integral value of the amount of unshared memory residing in the 110stack segment of a process (expressed in units of 111kilobytes * ticks-of-execution). 112.It Fa ru_minflt 113the number of page faults serviced without any I/O activity; here 114I/O activity is avoided by 115.Dq reclaiming 116a page frame from 117the list of pages awaiting reallocation. 118.It Fa ru_majflt 119the number of page faults serviced that required I/O activity. 120.It Fa ru_nswap 121the number of times a process was 122.Dq swapped 123out of main 124memory. 125.It Fa ru_inblock 126the number of times the file system had to perform input. 127.It Fa ru_oublock 128the number of times the file system had to perform output. 129.It Fa ru_msgsnd 130the number of IPC messages sent. 131.It Fa ru_msgrcv 132the number of IPC messages received. 133.It Fa ru_nsignals 134the number of signals delivered. 135.It Fa ru_nvcsw 136the number of times a context switch resulted due to a process 137voluntarily giving up the processor before its time slice was 138completed (usually to await availability of a resource). 139.It Fa ru_nivcsw 140the number of times a context switch resulted due to a higher 141priority process becoming runnable or because the current process 142exceeded its time slice. 143.El 144.Sh NOTES 145The numbers 146.Fa ru_inblock 147and 148.Fa ru_oublock 149account only for real 150I/O; data supplied by the caching mechanism is charged only 151to the first process to read or write the data. 152.Sh RETURN VALUES 153.Rv -std getrusage 154.Sh ERRORS 155The 156.Fn getrusage 157system call will fail if: 158.Bl -tag -width Er 159.It Bq Er EINVAL 160The 161.Fa who 162argument is not a valid value. 163.It Bq Er EFAULT 164The address specified by the 165.Fa rusage 166argument is not in a valid part of the process address space. 167.El 168.Sh SEE ALSO 169.Xr gettimeofday 2 , 170.Xr wait 2 , 171.Xr clocks 7 172.Sh HISTORY 173The 174.Fn getrusage 175system call appeared in 176.Bx 4.2 . 177The 178.Dv RUSAGE_THREAD 179facility first appeared in 180.Fx 8.1 . 181.Sh BUGS 182There is no way to obtain information about a child process 183that has not yet terminated. 184