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Diffstat (limited to 'lib/libc/sys/getrusage.2')
| -rw-r--r-- | lib/libc/sys/getrusage.2 | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/lib/libc/sys/getrusage.2 b/lib/libc/sys/getrusage.2 new file mode 100644 index 0000000..bdf5d45 --- /dev/null +++ b/lib/libc/sys/getrusage.2 @@ -0,0 +1,180 @@ +.\" Copyright (c) 1985, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)getrusage.2 8.1 (Berkeley) 6/4/93 +.\" $FreeBSD$ +.\" +.Dd June 4, 1993 +.Dt GETRUSAGE 2 +.Os +.Sh NAME +.Nm getrusage +.Nd get information about resource utilization +.Sh LIBRARY +.Lb libc +.Sh SYNOPSIS +.In sys/types.h +.In sys/time.h +.In sys/resource.h +.Fd "#define RUSAGE_SELF 0" +.Fd "#define RUSAGE_CHILDREN -1" +.Ft int +.Fn getrusage "int who" "struct rusage *rusage" +.Sh DESCRIPTION +The +.Fn getrusage +system call +returns information describing the resources utilized by the current +process, or all its terminated child processes. +The +.Fa who +argument is either +.Dv RUSAGE_SELF +or +.Dv RUSAGE_CHILDREN . +The buffer to which +.Fa rusage +points will be filled in with +the following structure: +.Bd -literal +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 */ +}; +.Ed +.Pp +The fields are interpreted as follows: +.Bl -tag -width ru_minfltaa +.It Fa ru_utime +the total amount of time spent executing in user mode. +.It Fa ru_stime +the total amount of time spent in the system executing on behalf +of the process(es). +.It Fa ru_maxrss +the maximum resident set size utilized (in kilobytes). +.It Fa ru_ixrss +an +.Dq 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. +Ticks are statistics clock ticks. +The statistics clock has a frequency of +.Fn sysconf _SC_CLK_TCK +ticks per second. +.It Fa 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). +.It Fa 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). +.It Fa ru_minflt +the number of page faults serviced without any I/O activity; here +I/O activity is avoided by +.Dq reclaiming +a page frame from +the list of pages awaiting reallocation. +.It Fa ru_majflt +the number of page faults serviced that required I/O activity. +.It Fa ru_nswap +the number of times a process was +.Dq swapped +out of main +memory. +.It Fa ru_inblock +the number of times the file system had to perform input. +.It Fa ru_oublock +the number of times the file system had to perform output. +.It Fa ru_msgsnd +the number of IPC messages sent. +.It Fa ru_msgrcv +the number of IPC messages received. +.It Fa ru_nsignals +the number of signals delivered. +.It Fa 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). +.It Fa 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. +.El +.Sh NOTES +The numbers +.Fa ru_inblock +and +.Fa 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. +.Sh RETURN VALUES +.Rv -std getrusage +.Sh ERRORS +The +.Fn getrusage +system call will fail if: +.Bl -tag -width Er +.It Bq Er EINVAL +The +.Fa who +argument is not a valid value. +.It Bq Er EFAULT +The address specified by the +.Fa rusage +argument is not in a valid part of the process address space. +.El +.Sh SEE ALSO +.Xr gettimeofday 2 , +.Xr wait 2 , +.Xr clocks 7 +.Sh HISTORY +The +.Fn getrusage +system call appeared in +.Bx 4.2 . +.Sh BUGS +There is no way to obtain information about a child process +that has not yet terminated. |
