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diff --git a/share/doc/psd/05.sysman/1.6.t b/share/doc/psd/05.sysman/1.6.t new file mode 100644 index 00000000000..109d2714f54 --- /dev/null +++ b/share/doc/psd/05.sysman/1.6.t @@ -0,0 +1,135 @@ +.\" Copyright (c) 1983, 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. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 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. +.\" +.\" @(#)1.6.t 8.1 (Berkeley) 6/8/93 +.\" +.sh "Resource controls +.NH 3 +Process priorities +.PP +The system gives CPU scheduling priority to processes that have not used +CPU time recently. This tends to favor interactive processes and +processes that execute only for short periods. +It is possible to determine the priority currently +assigned to a process, process group, or the processes of a specified user, +or to alter this priority using the calls: +.DS +._d +#define PRIO_PROCESS 0 /* process */ +#define PRIO_PGRP 1 /* process group */ +#define PRIO_USER 2 /* user id */ + +prio = getpriority(which, who); +result int prio; int which, who; + +setpriority(which, who, prio); +int which, who, prio; +.DE +The value \fIprio\fP is in the range \-20 to 20. +The default priority is 0; lower priorities cause more +favorable execution. +The \fIgetpriority\fP call returns the highest priority (lowest numerical value) +enjoyed by any of the specified processes. +The \fIsetpriority\fP call sets the priorities of all of the +specified processes to the specified value. +Only the super-user may lower priorities. +.NH 3 +Resource utilization +.PP +The resources used by a process are returned by a \fIgetrusage\fP call, +returning information in a structure defined in \fI<sys/resource.h>\fP: +.DS +._d +#define RUSAGE_SELF 0 /* usage by this process */ +#define RUSAGE_CHILDREN -1 /* usage by all children */ + +getrusage(who, rusage) +int who; result struct rusage *rusage; + +._f +struct rusage { + struct timeval ru_utime; /* user time used */ + struct timeval ru_stime; /* system time used */ + int ru_maxrss; /* maximum core resident set size: kbytes */ + int ru_ixrss; /* integral shared memory size (kbytes*sec) */ + int ru_idrss; /* unshared data memory size */ + int ru_isrss; /* unshared stack memory size */ + int ru_minflt; /* page-reclaims */ + int ru_majflt; /* page faults */ + int ru_nswap; /* swaps */ + int ru_inblock; /* block input operations */ + int ru_oublock; /* block output operations */ + int ru_msgsnd; /* messages sent */ + int ru_msgrcv; /* messages received */ + int ru_nsignals; /* signals received */ + int ru_nvcsw; /* voluntary context switches */ + int ru_nivcsw; /* involuntary context switches */ +}; +.DE +The \fIwho\fP parameter specifies whose resource usage is to be returned. +The resources used by the current process, or by all +the terminated children of the current process may be requested. +.NH 3 +Resource limits +.PP +The resources of a process for which limits are controlled by the +kernel are defined in \fI<sys/resource.h>\fP, and controlled by the +\fIgetrlimit\fP and \fIsetrlimit\fP calls: +.DS +._d +#define RLIMIT_CPU 0 /* cpu time in milliseconds */ +#define RLIMIT_FSIZE 1 /* maximum file size */ +#define RLIMIT_DATA 2 /* maximum data segment size */ +#define RLIMIT_STACK 3 /* maximum stack segment size */ +#define RLIMIT_CORE 4 /* maximum core file size */ +#define RLIMIT_RSS 5 /* maximum resident set size */ + +#define RLIM_NLIMITS 6 + +#define RLIM_INFINITY 0x7f\&f\&f\&f\&f\&f\&f + +._f +struct rlimit { + int rlim_cur; /* current (soft) limit */ + int rlim_max; /* hard limit */ +}; + +getrlimit(resource, rlp) +int resource; result struct rlimit *rlp; + +setrlimit(resource, rlp) +int resource; struct rlimit *rlp; +.DE +.PP +Only the super-user can raise the maximum limits. +Other users may only +alter \fIrlim_cur\fP within the range from 0 to \fIrlim_max\fP +or (irreversibly) lower \fIrlim_max\fP. |