2004-11-03 13:51:07 +00:00
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.\" Copyright (C) Tom Bjorkholm, Markus Kuhn & David A. Wheeler 1996-1999
|
2007-07-20 13:35:31 +00:00
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|
.\" and Copyright (C) 2007 Carsten Emde <Carsten.Emde@osadl.org>
|
2008-06-12 05:43:11 +00:00
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|
.\" and Copyright (C) 2008 Michael Kerrisk <mtk.manpages@gmail.com>
|
2004-11-03 13:51:07 +00:00
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.\"
|
getent.1, _syscall.2, acct.2, adjtimex.2, bdflush.2, brk.2, cacheflush.2, getsid.2, getxattr.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, ioperm.2, ipc.2, listxattr.2, mlock.2, modify_ldt.2, mremap.2, nanosleep.2, outb.2, perf_event_open.2, ptrace.2, removexattr.2, s390_runtime_instr.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, setsid.2, setxattr.2, socketcall.2, unimplemented.2, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, cfree.3, crypt.3, dlopen.3, encrypt.3, errno.3, fenv.3, ftime.3, ftw.3, getgrent_r.3, getpass.3, getpwent_r.3, getutent.3, hsearch.3, lio_listio.3, lockf.3, login.3, longjmp.3, perror.3, printf.3, scandirat.3, setjmp.3, strfmon.3, strtoimax.3, termios.3, ttyname.3, ualarm.3, updwtmp.3, wcstoimax.3, wordexp.3, console_ioctl.4, dsp56k.4, fd.4, hd.4, intro.4, lp.4, mem.4, null.4, ram.4, rtc.4, sk98lin.4, tty.4, ttyS.4, vcs.4, filesystems.5, group.5, host.conf.5, hosts.5, intro.5, issue.5, motd.5, networks.5, nologin.5, nsswitch.conf.5, passwd.5, proc.5, protocols.5, securetty.5, shells.5, termcap.5, ttytype.5, utmp.5, intro.6, armscii-8.7, ascii.7, bootparam.7, cp1251.7, environ.7, glob.7, intro.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, posixoptions.7, standards.7, unicode.7, utf-8.7, intro.8: s/GPLv2+_doc_full/GPLv2+_DOC_FULL/
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:29:46 +00:00
|
|
|
.\" %%%LICENSE_START(GPLv2+_DOC_FULL)
|
2004-11-03 13:51:07 +00:00
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|
.\" This is free documentation; you can redistribute it and/or
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|
.\" modify it under the terms of the GNU General Public License as
|
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.\" published by the Free Software Foundation; either version 2 of
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.\" the License, or (at your option) any later version.
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.\"
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|
|
.\" The GNU General Public License's references to "object code"
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.\" and "executables" are to be interpreted as the output of any
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.\" document formatting or typesetting system, including
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.\" intermediate and printed output.
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.\"
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.\" This manual is distributed in the hope that it will be useful,
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.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
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.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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.\" GNU General Public License for more details.
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.\"
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.\" You should have received a copy of the GNU General Public
|
getent.1, _syscall.2, acct.2, adjtimex.2, bdflush.2, brk.2, cacheflush.2, getsid.2, getxattr.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, ioperm.2, ipc.2, listxattr.2, mlock.2, modify_ldt.2, mremap.2, nanosleep.2, outb.2, ptrace.2, removexattr.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, setsid.2, setxattr.2, socketcall.2, unimplemented.2, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, cfree.3, crypt.3, dlopen.3, errno.3, fenv.3, ftime.3, ftw.3, getgrent_r.3, getpass.3, getpwent_r.3, getutent.3, hsearch.3, lio_listio.3, login.3, longjmp.3, perror.3, printf.3, scandirat.3, setjmp.3, strfmon.3, strtoimax.3, termios.3, ttyname.3, ualarm.3, wcstoimax.3, wordexp.3, console_ioctl.4, dsp56k.4, fd.4, hd.4, intro.4, lp.4, mem.4, null.4, ram.4, rtc.4, sk98lin.4, tty.4, ttyS.4, vcs.4, charmap.5, filesystems.5, ftpusers.5, gai.conf.5, group.5, host.conf.5, hosts.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, nss.5, nsswitch.conf.5, passwd.5, proc.5, protocols.5, securetty.5, shells.5, termcap.5, ttytype.5, utmp.5, intro.6, armscii-8.7, ascii.7, bootparam.7, cp1251.7, cpuset.7, environ.7, glob.7, intro.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, posixoptions.7, standards.7, unicode.7, utf-8.7, intro.8, ldconfig.8, nscd.8: Global fix: Update info in source comments on where to get a copy of the GPL
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:28:43 +00:00
|
|
|
.\" License along with this manual; if not, see
|
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|
.\" <http://www.gnu.org/licenses/>.
|
getent.1, _syscall.2, acct.2, adjtimex.2, bdflush.2, brk.2, cacheflush.2, getsid.2, getxattr.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, ioperm.2, ipc.2, listxattr.2, mlock.2, modify_ldt.2, mremap.2, nanosleep.2, outb.2, perf_event_open.2, ptrace.2, removexattr.2, s390_runtime_instr.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, setsid.2, setxattr.2, socketcall.2, unimplemented.2, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, cfree.3, crypt.3, dlopen.3, encrypt.3, errno.3, fenv.3, ftime.3, ftw.3, getgrent_r.3, getpass.3, getpwent_r.3, getutent.3, hsearch.3, lio_listio.3, lockf.3, login.3, longjmp.3, perror.3, printf.3, scandirat.3, setjmp.3, strfmon.3, strtoimax.3, termios.3, ttyname.3, ualarm.3, updwtmp.3, wcstoimax.3, wordexp.3, console_ioctl.4, dsp56k.4, fd.4, hd.4, intro.4, lp.4, mem.4, null.4, ram.4, rtc.4, sk98lin.4, tty.4, ttyS.4, vcs.4, filesystems.5, group.5, host.conf.5, hosts.5, intro.5, issue.5, motd.5, networks.5, nologin.5, nsswitch.conf.5, passwd.5, proc.5, protocols.5, securetty.5, shells.5, termcap.5, ttytype.5, utmp.5, intro.6, armscii-8.7, ascii.7, bootparam.7, cp1251.7, environ.7, glob.7, intro.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, posixoptions.7, standards.7, unicode.7, utf-8.7, intro.8: Global fix: Add LICENSE_START(GPLv2+_doc_full)
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:28:44 +00:00
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.\" %%%LICENSE_END
|
2004-11-03 13:51:07 +00:00
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.\"
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.\" 1996-04-01 Tom Bjorkholm <tomb@mydata.se>
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.\" First version written
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.\" 1996-04-10 Markus Kuhn <mskuhn@cip.informatik.uni-erlangen.de>
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.\" revision
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.\" 1999-08-18 David A. Wheeler <dwheeler@ida.org> added Note.
|
2007-09-20 06:52:22 +00:00
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.\" Modified, 25 Jun 2002, Michael Kerrisk <mtk.manpages@gmail.com>
|
2007-04-12 22:42:49 +00:00
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.\" Corrected description of queue placement by sched_setparam() and
|
2004-11-03 13:51:07 +00:00
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.\" sched_setscheduler()
|
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.\" A couple of grammar clean-ups
|
2007-09-20 06:52:22 +00:00
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.\" Modified 2004-05-27 by Michael Kerrisk <mtk.manpages@gmail.com>
|
2006-03-23 01:06:07 +00:00
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.\" 2005-03-23, mtk, Added description of SCHED_BATCH.
|
2007-07-20 13:35:31 +00:00
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.\" 2007-07-10, Carsten Emde <Carsten.Emde@osadl.org>
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.\" Add text on real-time features that are currently being
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.\" added to the mainline kernel.
|
2008-06-12 11:52:08 +00:00
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.\" 2008-05-07, mtk; Rewrote and restructured various parts of the page to
|
2008-06-12 05:43:11 +00:00
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.\" improve readability.
|
2010-06-19 04:48:45 +00:00
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.\" 2010-06-19, mtk, documented SCHED_RESET_ON_FORK
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2004-11-03 13:51:07 +00:00
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.\"
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2008-11-06 19:10:03 +00:00
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.\" Worth looking at: http://rt.wiki.kernel.org/index.php
|
2008-07-14 18:50:30 +00:00
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.\"
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fork.2, getpriority.2, ioprio_set.2, sched_setparam.2, sched_setscheduler.2, shmop.2, sigaction.2, unimplemented.2, makecontext.3, sysconf.3, resolv.conf.5, cpuset.7, ip.7, svipc.7, termio.7, zdump.8: tstamp
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-12 02:51:12 +00:00
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.TH SCHED_SETSCHEDULER 2 2013-02-12 "Linux" "Linux Programmer's Manual"
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2004-11-03 13:51:07 +00:00
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.SH NAME
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sched_setscheduler, sched_getscheduler \-
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2008-06-12 05:43:11 +00:00
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set and get scheduling policy/parameters
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2004-11-03 13:51:07 +00:00
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.SH SYNOPSIS
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2006-03-23 01:06:07 +00:00
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.nf
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2004-11-03 13:51:07 +00:00
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.B #include <sched.h>
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.sp
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.BI "int sched_setscheduler(pid_t " pid ", int " policy ,
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2006-03-23 01:06:07 +00:00
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.br
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.BI " const struct sched_param *" param );
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2004-11-03 13:51:07 +00:00
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.sp
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.BI "int sched_getscheduler(pid_t " pid );
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.sp
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\fBstruct sched_param {
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2006-03-23 01:06:07 +00:00
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...
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int \fIsched_priority\fB;
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...
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2004-11-03 13:51:07 +00:00
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};
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.fi
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.SH DESCRIPTION
|
2005-10-19 06:54:38 +00:00
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.BR sched_setscheduler ()
|
2004-11-03 13:51:07 +00:00
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sets both the scheduling policy and the associated parameters for the
|
2008-06-12 05:43:11 +00:00
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process whose ID is specified in \fIpid\fP.
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2007-04-12 22:42:49 +00:00
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If \fIpid\fP equals zero, the
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2008-06-12 05:43:11 +00:00
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scheduling policy and parameters of the calling process will be set.
|
2007-04-12 22:42:49 +00:00
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The interpretation of
|
2008-07-10 20:10:28 +00:00
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the argument \fIparam\fP depends on the selected policy.
|
2008-06-16 08:41:43 +00:00
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Currently, Linux supports the following "normal"
|
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(i.e., non-real-time) scheduling policies:
|
2008-06-12 05:43:11 +00:00
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.TP 14
|
2008-06-12 11:52:08 +00:00
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.BR SCHED_OTHER
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the standard round-robin time-sharing policy;
|
2007-04-12 22:42:49 +00:00
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.\" In the 2.6 kernel sources, SCHED_OTHER is actually called
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2006-03-23 01:06:07 +00:00
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.\" SCHED_NORMAL.
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2008-06-12 05:43:11 +00:00
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.TP
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.BR SCHED_BATCH
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for "batch" style execution of processes; and
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.TP
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.BR SCHED_IDLE
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for running
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.I very
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low priority background jobs.
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.PP
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The following "real-time" policies are also supported,
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for special time-critical applications that need precise control over
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the way in which runnable processes are selected for execution:
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.TP 14
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.BR SCHED_FIFO
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a first-in, first-out policy; and
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.TP
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.BR SCHED_RR
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a round-robin policy.
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.PP
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The semantics of each of these policies are detailed below.
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2004-11-03 13:51:07 +00:00
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2005-10-19 06:54:38 +00:00
|
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.BR sched_getscheduler ()
|
2004-11-03 13:51:07 +00:00
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queries the scheduling policy currently applied to the process
|
2007-04-12 22:42:49 +00:00
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identified by \fIpid\fP.
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If \fIpid\fP equals zero, the policy of the
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2004-11-03 13:51:07 +00:00
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calling process will be retrieved.
|
2008-06-12 05:43:11 +00:00
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.\"
|
intro.1, time.1, _syscall.2, accept.2, brk.2, capget.2, faccessat.2, futimesat.2, gethostname.2, intro.2, ioprio_set.2, kill.2, madvise.2, mlock.2, mount.2, msgget.2, perf_event_open.2, poll.2, readv.2, sched_rr_get_interval.2, sched_setscheduler.2, select.2, select_tut.2, shmget.2, stat.2, timer_create.2, ustat.2, vfork.2, wait.2, alloca.3, atexit.3, catopen.3, crypt.3, dbopen.3, fenv.3, fopen.3, getaddrinfo_a.3, gethostbyname.3, getutent.3, intro.3, login.3, mallopt.3, queue.3, regex.3, sigpause.3, sigsetops.3, stdio.3, strftime.3, strptime.3, sysconf.3, ttyslot.3, undocumented.3, cciss.4, console_codes.4, hpsa.4, initrd.4, intro.4, rtc.4, st.4, tty_ioctl.4, wavelan.4, acct.5, charmap.5, dir_colors.5, hosts.5, intro.5, termcap.5, utmp.5, intro.6, armscii-8.7, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, ddp.7, epoll.7, glob.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, man-pages.7, man.7, math_error.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, pthreads.7, raw.7, rtnetlink.7, signal.7, socket.7, spufs.7, svipc.7, tcp.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, intro.8: Global fix: use consistent capitalization in .SS headings
Capitalization in .SS sections across pages (and sometimes even
within a single page) is wildly inconsistent. Make it consistent.
Capitalize first word in heading, but otherwise use lower case,
except where English usage (e.g., proper nouns) or programming
language requirements (e.g., identifier names) dictate otherwise.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 14:08:38 +00:00
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.SS Scheduling policies
|
2008-06-12 05:43:11 +00:00
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The scheduler is the kernel component that decides which runnable process
|
2007-04-12 22:42:49 +00:00
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|
will be executed by the CPU next.
|
2008-06-12 05:43:11 +00:00
|
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|
Each process has an associated scheduling policy and a \fIstatic\fP
|
|
|
|
scheduling priority, \fIsched_priority\fP; these are the settings
|
|
|
|
that are modified by
|
|
|
|
.BR sched_setscheduler ().
|
|
|
|
The scheduler makes it decisions based on knowledge of the scheduling
|
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|
policy and static priority of all processes on the system.
|
2004-11-03 13:51:07 +00:00
|
|
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2008-06-12 05:43:11 +00:00
|
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For processes scheduled under one of the normal scheduling policies
|
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|
(\fBSCHED_OTHER\fP, \fBSCHED_IDLE\fP, \fBSCHED_BATCH\fP),
|
|
|
|
\fIsched_priority\fP is not used in scheduling
|
|
|
|
decisions (it must be specified as 0).
|
2006-03-23 01:06:07 +00:00
|
|
|
|
2008-06-12 11:52:08 +00:00
|
|
|
Processes scheduled under one of the real-time policies
|
2008-06-12 05:43:11 +00:00
|
|
|
(\fBSCHED_FIFO\fP, \fBSCHED_RR\fP) have a
|
|
|
|
\fIsched_priority\fP value in the range 1 (low) to 99 (high).
|
|
|
|
(As the numbers imply, real-time processes always have higher priority
|
|
|
|
than normal processes.)
|
|
|
|
Note well: POSIX.1-2001 only requires an implementation to support a
|
|
|
|
minimum 32 distinct priority levels for the real-time policies,
|
2008-07-02 11:58:38 +00:00
|
|
|
and some systems supply just this minimum.
|
2008-06-12 05:43:11 +00:00
|
|
|
Portable programs should use
|
2007-05-12 09:06:04 +00:00
|
|
|
.BR sched_get_priority_min (2)
|
|
|
|
and
|
|
|
|
.BR sched_get_priority_max (2)
|
2008-06-12 05:43:11 +00:00
|
|
|
to find the range of priorities supported for a particular policy.
|
2004-11-03 13:51:07 +00:00
|
|
|
|
2008-06-12 05:43:11 +00:00
|
|
|
Conceptually, the scheduler maintains a list of runnable
|
|
|
|
processes for each possible \fIsched_priority\fP value.
|
|
|
|
In order to determine which process runs next, the scheduler looks for
|
mbind.2, rename.2, sched_setscheduler.2, set_mempolicy.2, syslog.2, argz_add.3, dlopen.3, scanf.3, strtod.3, strtok.3, tcgetpgrp.3, hd.4, cpuset.7, regex.7, ld.so.8: Global fix: s/non-empty/nonempty/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:41:47 +00:00
|
|
|
the nonempty list with the highest static priority and selects the
|
2008-06-12 05:43:11 +00:00
|
|
|
process at the head of this list.
|
|
|
|
|
|
|
|
A process's scheduling policy determines
|
|
|
|
where it will be inserted into the list of processes
|
|
|
|
with equal static priority and how it will move inside this list.
|
|
|
|
|
|
|
|
All scheduling is preemptive: if a process with a higher static
|
|
|
|
priority becomes ready to run, the currently running process
|
|
|
|
will be preempted and
|
|
|
|
returned to the wait list for its static priority level.
|
2007-04-12 22:42:49 +00:00
|
|
|
The scheduling policy only determines the
|
2004-11-03 13:51:07 +00:00
|
|
|
ordering within the list of runnable processes with equal static
|
|
|
|
priority.
|
intro.1, time.1, _syscall.2, accept.2, brk.2, capget.2, faccessat.2, futimesat.2, gethostname.2, intro.2, ioprio_set.2, kill.2, madvise.2, mlock.2, mount.2, msgget.2, perf_event_open.2, poll.2, readv.2, sched_rr_get_interval.2, sched_setscheduler.2, select.2, select_tut.2, shmget.2, stat.2, timer_create.2, ustat.2, vfork.2, wait.2, alloca.3, atexit.3, catopen.3, crypt.3, dbopen.3, fenv.3, fopen.3, getaddrinfo_a.3, gethostbyname.3, getutent.3, intro.3, login.3, mallopt.3, queue.3, regex.3, sigpause.3, sigsetops.3, stdio.3, strftime.3, strptime.3, sysconf.3, ttyslot.3, undocumented.3, cciss.4, console_codes.4, hpsa.4, initrd.4, intro.4, rtc.4, st.4, tty_ioctl.4, wavelan.4, acct.5, charmap.5, dir_colors.5, hosts.5, intro.5, termcap.5, utmp.5, intro.6, armscii-8.7, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, ddp.7, epoll.7, glob.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, man-pages.7, man.7, math_error.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, pthreads.7, raw.7, rtnetlink.7, signal.7, socket.7, spufs.7, svipc.7, tcp.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, intro.8: Global fix: use consistent capitalization in .SS headings
Capitalization in .SS sections across pages (and sometimes even
within a single page) is wildly inconsistent. Make it consistent.
Capitalize first word in heading, but otherwise use lower case,
except where English usage (e.g., proper nouns) or programming
language requirements (e.g., identifier names) dictate otherwise.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 14:08:38 +00:00
|
|
|
.SS SCHED_FIFO: First in-first out scheduling
|
2007-06-20 22:11:14 +00:00
|
|
|
\fBSCHED_FIFO\fP can only be used with static priorities higher than
|
|
|
|
0, which means that when a \fBSCHED_FIFO\fP processes becomes runnable,
|
2006-03-23 01:06:07 +00:00
|
|
|
it will always immediately preempt any currently running
|
2008-03-03 14:20:27 +00:00
|
|
|
\fBSCHED_OTHER\fP, \fBSCHED_BATCH\fP, or \fBSCHED_IDLE\fP process.
|
2007-06-20 22:11:14 +00:00
|
|
|
\fBSCHED_FIFO\fP is a simple scheduling
|
2007-04-12 22:42:49 +00:00
|
|
|
algorithm without time slicing.
|
|
|
|
For processes scheduled under the
|
2008-06-12 05:43:11 +00:00
|
|
|
\fBSCHED_FIFO\fP policy, the following rules apply:
|
|
|
|
.IP * 3
|
|
|
|
A \fBSCHED_FIFO\fP process that has been preempted by another process of
|
2004-11-03 13:51:07 +00:00
|
|
|
higher priority will stay at the head of the list for its priority and
|
|
|
|
will resume execution as soon as all processes of higher priority are
|
2007-04-12 22:42:49 +00:00
|
|
|
blocked again.
|
2008-06-12 05:43:11 +00:00
|
|
|
.IP *
|
2007-06-20 22:11:14 +00:00
|
|
|
When a \fBSCHED_FIFO\fP process becomes runnable, it
|
2007-04-12 22:42:49 +00:00
|
|
|
will be inserted at the end of the list for its priority.
|
2008-06-12 05:43:11 +00:00
|
|
|
.IP *
|
2007-04-12 22:42:49 +00:00
|
|
|
A call to
|
2007-05-12 09:06:04 +00:00
|
|
|
.BR sched_setscheduler ()
|
|
|
|
or
|
|
|
|
.BR sched_setparam (2)
|
|
|
|
will put the
|
2007-06-20 22:11:14 +00:00
|
|
|
\fBSCHED_FIFO\fP (or \fBSCHED_RR\fP) process identified by
|
2004-11-03 13:51:07 +00:00
|
|
|
\fIpid\fP at the start of the list if it was runnable.
|
|
|
|
As a consequence, it may preempt the currently running process if
|
|
|
|
it has the same priority.
|
2006-08-04 12:39:17 +00:00
|
|
|
(POSIX.1-2001 specifies that the process should go to the end
|
2004-11-03 13:51:07 +00:00
|
|
|
of the list.)
|
|
|
|
.\" In 2.2.x and 2.4.x, the process is placed at the front of the queue
|
|
|
|
.\" In 2.0.x, the Right Thing happened: the process went to the back -- MTK
|
2008-06-12 05:43:11 +00:00
|
|
|
.IP *
|
2007-05-12 09:06:04 +00:00
|
|
|
A process calling
|
|
|
|
.BR sched_yield (2)
|
2008-06-12 05:43:11 +00:00
|
|
|
will be put at the end of the list.
|
|
|
|
.PP
|
2007-04-12 22:42:49 +00:00
|
|
|
No other events will move a process
|
2007-06-20 22:11:14 +00:00
|
|
|
scheduled under the \fBSCHED_FIFO\fP policy in the wait list of
|
2007-04-12 22:42:49 +00:00
|
|
|
runnable processes with equal static priority.
|
2008-06-12 05:43:11 +00:00
|
|
|
|
2007-06-20 22:11:14 +00:00
|
|
|
A \fBSCHED_FIFO\fP
|
2004-11-03 13:51:07 +00:00
|
|
|
process runs until either it is blocked by an I/O request, it is
|
2007-05-12 09:06:04 +00:00
|
|
|
preempted by a higher priority process, or it calls
|
|
|
|
.BR sched_yield (2).
|
intro.1, time.1, _syscall.2, accept.2, brk.2, capget.2, faccessat.2, futimesat.2, gethostname.2, intro.2, ioprio_set.2, kill.2, madvise.2, mlock.2, mount.2, msgget.2, perf_event_open.2, poll.2, readv.2, sched_rr_get_interval.2, sched_setscheduler.2, select.2, select_tut.2, shmget.2, stat.2, timer_create.2, ustat.2, vfork.2, wait.2, alloca.3, atexit.3, catopen.3, crypt.3, dbopen.3, fenv.3, fopen.3, getaddrinfo_a.3, gethostbyname.3, getutent.3, intro.3, login.3, mallopt.3, queue.3, regex.3, sigpause.3, sigsetops.3, stdio.3, strftime.3, strptime.3, sysconf.3, ttyslot.3, undocumented.3, cciss.4, console_codes.4, hpsa.4, initrd.4, intro.4, rtc.4, st.4, tty_ioctl.4, wavelan.4, acct.5, charmap.5, dir_colors.5, hosts.5, intro.5, termcap.5, utmp.5, intro.6, armscii-8.7, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, ddp.7, epoll.7, glob.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, man-pages.7, man.7, math_error.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, pthreads.7, raw.7, rtnetlink.7, signal.7, socket.7, spufs.7, svipc.7, tcp.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, intro.8: Global fix: use consistent capitalization in .SS headings
Capitalization in .SS sections across pages (and sometimes even
within a single page) is wildly inconsistent. Make it consistent.
Capitalize first word in heading, but otherwise use lower case,
except where English usage (e.g., proper nouns) or programming
language requirements (e.g., identifier names) dictate otherwise.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 14:08:38 +00:00
|
|
|
.SS SCHED_RR: Round-robin scheduling
|
2007-06-20 22:11:14 +00:00
|
|
|
\fBSCHED_RR\fP is a simple enhancement of \fBSCHED_FIFO\fP.
|
2007-04-12 22:42:49 +00:00
|
|
|
Everything
|
2007-06-20 22:11:14 +00:00
|
|
|
described above for \fBSCHED_FIFO\fP also applies to \fBSCHED_RR\fP,
|
2004-11-03 13:51:07 +00:00
|
|
|
except that each process is only allowed to run for a maximum time
|
2007-04-12 22:42:49 +00:00
|
|
|
quantum.
|
2007-06-20 22:11:14 +00:00
|
|
|
If a \fBSCHED_RR\fP process has been running for a time
|
2004-11-03 13:51:07 +00:00
|
|
|
period equal to or longer than the time quantum, it will be put at the
|
2007-04-12 22:42:49 +00:00
|
|
|
end of the list for its priority.
|
2007-06-20 22:11:14 +00:00
|
|
|
A \fBSCHED_RR\fP process that has
|
2004-11-03 13:51:07 +00:00
|
|
|
been preempted by a higher priority process and subsequently resumes
|
|
|
|
execution as a running process will complete the unexpired portion of
|
intro.1, time.1, _syscall.2, accept.2, brk.2, capget.2, faccessat.2, futimesat.2, gethostname.2, intro.2, ioprio_set.2, kill.2, madvise.2, mlock.2, mount.2, msgget.2, perf_event_open.2, poll.2, readv.2, sched_rr_get_interval.2, sched_setscheduler.2, select.2, select_tut.2, shmget.2, stat.2, timer_create.2, ustat.2, vfork.2, wait.2, alloca.3, atexit.3, catopen.3, crypt.3, dbopen.3, fenv.3, fopen.3, getaddrinfo_a.3, gethostbyname.3, getutent.3, intro.3, login.3, mallopt.3, queue.3, regex.3, sigpause.3, sigsetops.3, stdio.3, strftime.3, strptime.3, sysconf.3, ttyslot.3, undocumented.3, cciss.4, console_codes.4, hpsa.4, initrd.4, intro.4, rtc.4, st.4, tty_ioctl.4, wavelan.4, acct.5, charmap.5, dir_colors.5, hosts.5, intro.5, termcap.5, utmp.5, intro.6, armscii-8.7, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, ddp.7, epoll.7, glob.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, man-pages.7, man.7, math_error.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, pthreads.7, raw.7, rtnetlink.7, signal.7, socket.7, spufs.7, svipc.7, tcp.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, intro.8: Global fix: use consistent capitalization in .SS headings
Capitalization in .SS sections across pages (and sometimes even
within a single page) is wildly inconsistent. Make it consistent.
Capitalize first word in heading, but otherwise use lower case,
except where English usage (e.g., proper nouns) or programming
language requirements (e.g., identifier names) dictate otherwise.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 14:08:38 +00:00
|
|
|
its round-robin time quantum.
|
2007-04-12 22:42:49 +00:00
|
|
|
The length of the time quantum can be
|
2007-05-12 09:06:04 +00:00
|
|
|
retrieved using
|
|
|
|
.BR sched_rr_get_interval (2).
|
2004-11-03 13:51:07 +00:00
|
|
|
.\" On Linux 2.4, the length of the RR interval is influenced
|
|
|
|
.\" by the process nice value -- MTK
|
2006-03-12 01:39:10 +00:00
|
|
|
.\"
|
2004-11-03 13:51:07 +00:00
|
|
|
.SS SCHED_OTHER: Default Linux time-sharing scheduling
|
2007-06-20 22:11:14 +00:00
|
|
|
\fBSCHED_OTHER\fP can only be used at static priority 0.
|
|
|
|
\fBSCHED_OTHER\fP is the standard Linux time-sharing scheduler that is
|
2008-06-12 05:43:11 +00:00
|
|
|
intended for all processes that do not require the special
|
2007-04-12 22:42:49 +00:00
|
|
|
real-time mechanisms.
|
|
|
|
The process to run is chosen from the static
|
2008-06-12 05:43:11 +00:00
|
|
|
priority 0 list based on a \fIdynamic\fP priority that is determined only
|
2007-04-12 22:42:49 +00:00
|
|
|
inside this list.
|
2008-06-12 05:43:11 +00:00
|
|
|
The dynamic priority is based on the nice value (set by
|
2007-05-12 09:06:04 +00:00
|
|
|
.BR nice (2)
|
|
|
|
or
|
|
|
|
.BR setpriority (2))
|
2008-06-12 05:43:11 +00:00
|
|
|
and increased for each time quantum the process is ready to run,
|
|
|
|
but denied to run by the scheduler.
|
|
|
|
This ensures fair progress among all \fBSCHED_OTHER\fP processes.
|
|
|
|
.\"
|
2006-03-23 01:06:07 +00:00
|
|
|
.SS SCHED_BATCH: Scheduling batch processes
|
|
|
|
(Since Linux 2.6.16.)
|
2007-06-20 22:11:14 +00:00
|
|
|
\fBSCHED_BATCH\fP can only be used at static priority 0.
|
2008-03-05 15:22:09 +00:00
|
|
|
This policy is similar to \fBSCHED_OTHER\fP in that it schedules
|
|
|
|
the process according to its dynamic priority
|
|
|
|
(based on the nice value).
|
|
|
|
The difference is that this policy
|
|
|
|
will cause the scheduler to always assume
|
2006-03-23 01:06:07 +00:00
|
|
|
that the process is CPU-intensive.
|
|
|
|
Consequently, the scheduler will apply a small scheduling
|
2008-03-03 14:20:27 +00:00
|
|
|
penalty with respect to wakeup behaviour,
|
|
|
|
so that this process is mildly disfavored in scheduling decisions.
|
2008-06-12 05:43:11 +00:00
|
|
|
|
2007-04-12 22:42:49 +00:00
|
|
|
.\" The following paragraph is drawn largely from the text that
|
|
|
|
.\" accompanied Ingo Molnar's patch for the implementation of
|
2006-03-23 01:06:07 +00:00
|
|
|
.\" SCHED_BATCH.
|
accept.2, access.2, acct.2, clock_nanosleep.2, mbind.2, mincore.2, remap_file_pages.2, sched_setscheduler.2, set_mempolicy.2, splice.2, stat.2, syslog.2, timer_create.2, timerfd_create.2, truncate.2, fenv.3, ferror.3, fflush.3, fgetwc.3, fgetws.3, flockfile.3, fputwc.3, fputws.3, fread.3, getopt.3, gets.3, getwchar.3, glob.3, iconv.3, longjmp.3, pow.3, printf.3, puts.3, putwchar.3, regex.3, rpc.3, scanf.3, setjmp.3, termios.3, unlocked_stdio.3, wcswidth.3, hd.4, rtc.4, st.4, core.5, dir_colors.5, elf.5, proc.5, arp.7, ascii.7, boot.7, bootparam.7, charsets.7, futex.7, ip.7, iso_8859-11.7, man-pages.7, man.7, mdoc.samples.7, path_resolution.7, pipe.7, posixoptions.7, unicode.7, unix.7, uri.7, utf-8.7, ld.so.8: s/non-/non/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 17:20:12 +00:00
|
|
|
This policy is useful for workloads that are noninteractive,
|
2007-04-12 22:42:49 +00:00
|
|
|
but do not want to lower their nice value,
|
|
|
|
and for workloads that want a deterministic scheduling policy without
|
2006-03-23 01:06:07 +00:00
|
|
|
interactivity causing extra preemptions (between the workload's tasks).
|
2008-03-03 14:20:27 +00:00
|
|
|
.\"
|
|
|
|
.SS SCHED_IDLE: Scheduling very low priority jobs
|
|
|
|
(Since Linux 2.6.23.)
|
|
|
|
\fBSCHED_IDLE\fP can only be used at static priority 0;
|
|
|
|
the process nice value has no influence for this policy.
|
2008-06-12 05:43:11 +00:00
|
|
|
|
2008-03-03 14:20:27 +00:00
|
|
|
This policy is intended for running jobs at extremely low
|
|
|
|
priority (lower even than a +19 nice value with the
|
|
|
|
.B SCHED_OTHER
|
|
|
|
or
|
|
|
|
.B SCHED_BATCH
|
|
|
|
policies).
|
|
|
|
.\"
|
2010-06-19 04:48:45 +00:00
|
|
|
.SS Resetting scheduling policy for child processes
|
|
|
|
Since Linux 2.6.32, the
|
|
|
|
.B SCHED_RESET_ON_FORK
|
|
|
|
flag can be ORed in
|
|
|
|
.I policy
|
|
|
|
when calling
|
|
|
|
.BR sched_setscheduler ().
|
|
|
|
As a result of including this flag, children created by
|
|
|
|
.BR fork (2)
|
|
|
|
do not inherit privileged scheduling policies.
|
|
|
|
This feature is intended for media-playback applications,
|
|
|
|
and can be used to prevent applications evading the
|
|
|
|
.BR RLIMIT_RTTIME
|
|
|
|
resource limit (see
|
|
|
|
.BR getrlimit (2))
|
|
|
|
by creating multiple child processes.
|
|
|
|
|
|
|
|
More precisely, if the
|
|
|
|
.BR SCHED_RESET_ON_FORK
|
|
|
|
flag is specified,
|
|
|
|
the following rules apply for subsequently created children:
|
|
|
|
.IP * 3
|
|
|
|
If the calling process has a scheduling policy of
|
|
|
|
.B SCHED_FIFO
|
|
|
|
or
|
|
|
|
.BR SCHED_RR ,
|
|
|
|
the policy is reset to
|
|
|
|
.BR SCHED_OTHER
|
|
|
|
in child processes.
|
|
|
|
.IP *
|
2010-08-29 05:58:29 +00:00
|
|
|
If the calling process has a negative nice value,
|
2010-06-19 04:48:45 +00:00
|
|
|
the nice value is reset to zero in child processes.
|
|
|
|
.PP
|
|
|
|
After the
|
|
|
|
.BR SCHED_RESET_ON_FORK
|
|
|
|
flag has been enabled,
|
|
|
|
it can only be reset if the process has the
|
|
|
|
.BR CAP_SYS_NICE
|
|
|
|
capability.
|
|
|
|
This flag is disabled in child processes created by
|
|
|
|
.BR fork (2).
|
|
|
|
|
|
|
|
The
|
|
|
|
.B SCHED_RESET_ON_FORK
|
|
|
|
flag is visible in the policy value returned by
|
|
|
|
.BR sched_getscheduler ()
|
|
|
|
.\"
|
2005-07-28 14:37:51 +00:00
|
|
|
.SS Privileges and resource limits
|
|
|
|
In Linux kernels before 2.6.12, only privileged
|
|
|
|
.RB ( CAP_SYS_NICE )
|
intro.1, time.1, adjtimex.2, capget.2, eventfd.2, fcntl.2, getrlimit.2, getsockopt.2, gettimeofday.2, intro.2, ioctl_list.2, ioperm.2, mlock.2, pivot_root.2, poll.2, prctl.2, ptrace.2, sched_setscheduler.2, select_tut.2, semget.2, sigaltstack.2, signalfd.2, sysctl.2, timer_settime.2, timerfd_create.2, wait.2, CPU_SET.3, argz_add.3, assert_perror.3, atexit.3, backtrace.3, bcmp.3, clearenv.3, ctime.3, dl_iterate_phdr.3, dlopen.3, ecvt.3, errno.3, error.3, ether_aton.3, exit.3, fenv.3, ferror.3, finite.3, flockfile.3, fnmatch.3, fpathconf.3, fpclassify.3, ftime.3, ftok.3, ftw.3, fwide.3, getaddrinfo.3, gethostbyname.3, getlogin.3, getnameinfo.3, getnetent.3, getopt.3, getprotoent.3, getrpcent.3, getservent.3, glob.3, hsearch.3, inet.3, isalpha.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, longjmp.3, lsearch.3, malloc.3, matherr.3, mblen.3, mbsinit.3, mbtowc.3, on_exit.3, printf.3, pthread_attr_init.3, pthread_attr_setaffinity_np.3, pthread_attr_setdetachstate.3, pthread_attr_setguardsize.3, pthread_attr_setinheritsched.3, pthread_attr_setschedparam.3, pthread_attr_setschedpolicy.3, pthread_attr_setscope.3, pthread_attr_setstack.3, pthread_attr_setstackaddr.3, pthread_attr_setstacksize.3, pthread_cancel.3, pthread_cleanup_push.3, pthread_equal.3, pthread_getattr_np.3, pthread_getcpuclockid.3, pthread_setaffinity_np.3, pthread_setcancelstate.3, pthread_setconcurrency.3, pthread_setschedparam.3, pthread_setschedprio.3, ptsname.3, putenv.3, putgrent.3, raise.3, rcmd.3, regex.3, rexec.3, rpc.3, rpmatch.3, rtnetlink.3, scandir.3, sem_init.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, signbit.3, stdio_ext.3, strtod.3, strtol.3, strtoul.3, system.3, termios.3, timeradd.3, tzset.3, ualarm.3, wctomb.3, xdr.3, st.4, tty_ioctl.4, core.5, elf.5, proc.5, bootparam.7, capabilities.7, icmp.7, ip.7, ipv6.7, math_error.7, mdoc.samples.7, mq_overview.7, pthreads.7, raw.7, regex.7, socket.7, tcp.7, tzselect.8: Global fix: s/non-zero/nonzero/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:40:55 +00:00
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processes can set a nonzero static priority (i.e., set a real-time
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2008-06-12 05:43:11 +00:00
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scheduling policy).
|
2005-09-20 14:52:34 +00:00
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The only change that an unprivileged process can make is to set the
|
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.B SCHED_OTHER
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policy, and this can only be done if the effective user ID of the caller of
|
2005-10-19 06:54:38 +00:00
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.BR sched_setscheduler ()
|
2007-04-12 22:42:49 +00:00
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matches the real or effective user ID of the target process
|
2005-09-20 14:52:34 +00:00
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(i.e., the process specified by
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.IR pid )
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whose policy is being changed.
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2005-07-28 14:37:51 +00:00
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Since Linux 2.6.12, the
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.B RLIMIT_RTPRIO
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2005-09-20 14:52:34 +00:00
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resource limit defines a ceiling on an unprivileged process's
|
2008-06-12 05:43:11 +00:00
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static priority for the
|
2005-07-28 14:37:51 +00:00
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.B SCHED_RR
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and
|
2007-09-20 16:26:31 +00:00
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.B SCHED_FIFO
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2005-07-28 14:37:51 +00:00
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policies.
|
2008-06-16 08:41:43 +00:00
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The rules for changing scheduling policy and priority are as follows:
|
2010-06-19 04:49:32 +00:00
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.IP * 3
|
intro.1, time.1, adjtimex.2, capget.2, eventfd.2, fcntl.2, getrlimit.2, getsockopt.2, gettimeofday.2, intro.2, ioctl_list.2, ioperm.2, mlock.2, pivot_root.2, poll.2, prctl.2, ptrace.2, sched_setscheduler.2, select_tut.2, semget.2, sigaltstack.2, signalfd.2, sysctl.2, timer_settime.2, timerfd_create.2, wait.2, CPU_SET.3, argz_add.3, assert_perror.3, atexit.3, backtrace.3, bcmp.3, clearenv.3, ctime.3, dl_iterate_phdr.3, dlopen.3, ecvt.3, errno.3, error.3, ether_aton.3, exit.3, fenv.3, ferror.3, finite.3, flockfile.3, fnmatch.3, fpathconf.3, fpclassify.3, ftime.3, ftok.3, ftw.3, fwide.3, getaddrinfo.3, gethostbyname.3, getlogin.3, getnameinfo.3, getnetent.3, getopt.3, getprotoent.3, getrpcent.3, getservent.3, glob.3, hsearch.3, inet.3, isalpha.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, longjmp.3, lsearch.3, malloc.3, matherr.3, mblen.3, mbsinit.3, mbtowc.3, on_exit.3, printf.3, pthread_attr_init.3, pthread_attr_setaffinity_np.3, pthread_attr_setdetachstate.3, pthread_attr_setguardsize.3, pthread_attr_setinheritsched.3, pthread_attr_setschedparam.3, pthread_attr_setschedpolicy.3, pthread_attr_setscope.3, pthread_attr_setstack.3, pthread_attr_setstackaddr.3, pthread_attr_setstacksize.3, pthread_cancel.3, pthread_cleanup_push.3, pthread_equal.3, pthread_getattr_np.3, pthread_getcpuclockid.3, pthread_setaffinity_np.3, pthread_setcancelstate.3, pthread_setconcurrency.3, pthread_setschedparam.3, pthread_setschedprio.3, ptsname.3, putenv.3, putgrent.3, raise.3, rcmd.3, regex.3, rexec.3, rpc.3, rpmatch.3, rtnetlink.3, scandir.3, sem_init.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, signbit.3, stdio_ext.3, strtod.3, strtol.3, strtoul.3, system.3, termios.3, timeradd.3, tzset.3, ualarm.3, wctomb.3, xdr.3, st.4, tty_ioctl.4, core.5, elf.5, proc.5, bootparam.7, capabilities.7, icmp.7, ip.7, ipv6.7, math_error.7, mdoc.samples.7, mq_overview.7, pthreads.7, raw.7, regex.7, socket.7, tcp.7, tzselect.8: Global fix: s/non-zero/nonzero/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:40:55 +00:00
|
|
|
If an unprivileged process has a nonzero
|
2005-09-20 14:52:34 +00:00
|
|
|
.B RLIMIT_RTPRIO
|
2007-04-12 22:42:49 +00:00
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soft limit, then it can change its scheduling policy and priority,
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subject to the restriction that the priority cannot be set to a
|
2008-06-16 08:41:43 +00:00
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value higher than the maximum of its current priority and its
|
2005-09-20 14:52:34 +00:00
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.B RLIMIT_RTPRIO
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soft limit.
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2008-06-16 08:41:43 +00:00
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.IP *
|
2007-04-12 22:42:49 +00:00
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If the
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2005-09-20 14:52:34 +00:00
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|
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.B RLIMIT_RTPRIO
|
2008-06-16 08:41:43 +00:00
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soft limit is 0, then the only permitted changes are to lower the priority,
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or to switch to a non-real-time policy.
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.IP *
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2007-04-12 22:42:49 +00:00
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Subject to the same rules,
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another unprivileged process can also make these changes,
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as long as the effective user ID of the process making the change
|
2005-09-20 14:52:34 +00:00
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matches the real or effective user ID of the target process.
|
2008-06-16 08:41:43 +00:00
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.IP *
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Special rules apply for the
|
2011-09-20 16:25:40 +00:00
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.BR SCHED_IDLE .
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In Linux kernels before 2.6.39,
|
2008-06-16 08:41:43 +00:00
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an unprivileged process operating under this policy cannot
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change its policy, regardless of the value of its
|
|
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|
.BR RLIMIT_RTPRIO
|
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resource limit.
|
2011-09-20 16:25:40 +00:00
|
|
|
In Linux kernels since 2.6.39,
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.\" commit c02aa73b1d18e43cfd79c2f193b225e84ca497c8
|
|
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|
an unprivileged process can switch to either the
|
|
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|
.BR SCHED_BATCH
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or the
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.BR SCHED_NORMAL
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policy so long as its nice value falls within the range permitted by its
|
|
|
|
.BR RLIMIT_NICE
|
|
|
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resource limit (see
|
|
|
|
.BR getrlimit (2)).
|
2008-06-16 08:41:43 +00:00
|
|
|
.PP
|
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|
Privileged
|
|
|
|
.RB ( CAP_SYS_NICE )
|
|
|
|
processes ignore the
|
|
|
|
.B RLIMIT_RTPRIO
|
|
|
|
limit; as with older kernels,
|
|
|
|
they can make arbitrary changes to scheduling policy and priority.
|
2005-07-28 14:37:51 +00:00
|
|
|
See
|
|
|
|
.BR getrlimit (2)
|
|
|
|
for further information on
|
|
|
|
.BR RLIMIT_RTPRIO .
|
2004-11-03 13:51:07 +00:00
|
|
|
.SS Response time
|
|
|
|
A blocked high priority process waiting for the I/O has a certain
|
2007-04-12 22:42:49 +00:00
|
|
|
response time before it is scheduled again.
|
|
|
|
The device driver writer
|
2004-11-03 13:51:07 +00:00
|
|
|
can greatly reduce this response time by using a "slow interrupt"
|
|
|
|
interrupt handler.
|
|
|
|
.\" as described in
|
|
|
|
.\" .BR request_irq (9).
|
|
|
|
.SS Miscellaneous
|
2008-06-12 05:43:11 +00:00
|
|
|
Child processes inherit the scheduling policy and parameters across a
|
2007-05-11 23:07:02 +00:00
|
|
|
.BR fork (2).
|
2008-06-12 05:43:11 +00:00
|
|
|
The scheduling policy and parameters are preserved across
|
2006-07-22 14:14:36 +00:00
|
|
|
.BR execve (2).
|
2004-11-03 13:51:07 +00:00
|
|
|
|
2007-04-12 22:42:49 +00:00
|
|
|
Memory locking is usually needed for real-time processes to avoid
|
2008-06-12 05:43:11 +00:00
|
|
|
paging delays; this can be done with
|
2007-05-11 23:07:02 +00:00
|
|
|
.BR mlock (2)
|
2007-04-12 22:42:49 +00:00
|
|
|
or
|
2007-05-11 23:07:02 +00:00
|
|
|
.BR mlockall (2).
|
2004-11-03 13:51:07 +00:00
|
|
|
|
accept.2, connect.2, eventfd.2, flock.2, open.2, posix_fadvise.2, read.2, recv.2, sched_setscheduler.2, select_tut.2, send.2, signalfd.2, splice.2, timerfd_create.2, write.2, flockfile.3, mkfifo.3, mq_notify.3, mq_open.3, pthread_tryjoin_np.3, scanf.3, random.4, ddp.7, epoll.7, fifo.7, ip.7, pipe.7, socket.7, spufs.7: Global fix: s/non-blocking/nonblocking/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:43:10 +00:00
|
|
|
Since a nonblocking infinite loop in a process scheduled under
|
2007-06-20 22:11:14 +00:00
|
|
|
\fBSCHED_FIFO\fP or \fBSCHED_RR\fP will block all processes with lower
|
2004-11-03 13:51:07 +00:00
|
|
|
priority forever, a software developer should always keep available on
|
|
|
|
the console a shell scheduled under a higher static priority than the
|
2007-04-12 22:42:49 +00:00
|
|
|
tested application.
|
|
|
|
This will allow an emergency kill of tested
|
2005-09-20 14:52:34 +00:00
|
|
|
real-time applications that do not block or terminate as expected.
|
2008-06-12 05:43:11 +00:00
|
|
|
See also the description of the
|
|
|
|
.BR RLIMIT_RTTIME
|
|
|
|
resource limit in
|
|
|
|
.BR getrlimit (2).
|
2004-11-03 13:51:07 +00:00
|
|
|
|
|
|
|
POSIX systems on which
|
2005-10-19 06:54:38 +00:00
|
|
|
.BR sched_setscheduler ()
|
2004-11-03 13:51:07 +00:00
|
|
|
and
|
2005-10-19 06:54:38 +00:00
|
|
|
.BR sched_getscheduler ()
|
2004-11-03 13:51:07 +00:00
|
|
|
are available define
|
2007-06-20 22:09:10 +00:00
|
|
|
.B _POSIX_PRIORITY_SCHEDULING
|
2007-06-20 21:53:34 +00:00
|
|
|
in \fI<unistd.h>\fP.
|
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH RETURN VALUE
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2004-11-03 13:51:07 +00:00
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On success,
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2005-10-19 06:54:38 +00:00
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.BR sched_setscheduler ()
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2007-04-12 22:42:49 +00:00
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returns zero.
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2004-11-03 13:51:07 +00:00
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On success,
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2005-10-19 06:54:38 +00:00
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.BR sched_getscheduler ()
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_syscall.2, accept.2, epoll_create.2, inotify_add_watch.2, ioctl.2, msgget.2, msgop.2, open.2, prctl.2, sched_setscheduler.2, semctl.2, semget.2, swapon.2, addseverity.3, cacosh.3, csqrt.3, dirfd.3, drand48.3, fputws.3, mq_send.3, posix_openpt.3, puts.3, sched_getcpu.3, shm_open.3, sqrt.3, sysconf.3, tgamma.3, ulimit.3, credentials.7, svipc.7: Global fix: s/non-negative/nonnegative/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:44:48 +00:00
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returns the policy for the process (a nonnegative integer).
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2006-03-23 01:06:07 +00:00
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On error, \-1 is returned, and
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2004-11-03 13:51:07 +00:00
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.I errno
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is set appropriately.
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.SH ERRORS
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.TP
|
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.B EINVAL
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The scheduling \fIpolicy\fP is not one of the recognized policies,
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2010-09-24 08:10:22 +00:00
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\fIparam\fP is NULL,
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2008-07-10 20:10:28 +00:00
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or \fIparam\fP does not make sense for the \fIpolicy\fP.
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2004-11-03 13:51:07 +00:00
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.TP
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.B EPERM
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2005-09-20 14:52:34 +00:00
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The calling process does not have appropriate privileges.
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2004-11-03 13:51:07 +00:00
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.TP
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.B ESRCH
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The process whose ID is \fIpid\fP could not be found.
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getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH CONFORMING TO
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2007-11-19 04:24:28 +00:00
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POSIX.1-2001 (but see BUGS below).
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2008-03-03 14:20:27 +00:00
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The \fBSCHED_BATCH\fP and \fBSCHED_IDLE\fP policies are Linux-specific.
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2006-03-23 01:06:07 +00:00
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.SH NOTES
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2007-06-16 12:25:22 +00:00
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POSIX.1 does not detail the permissions that an unprivileged
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process requires in order to call
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2007-07-08 14:57:58 +00:00
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.BR sched_setscheduler (),
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2007-06-16 12:25:22 +00:00
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and details vary across systems.
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For example, the Solaris 7 manual page says that
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2007-12-11 16:07:33 +00:00
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the real or effective user ID of the calling process must
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2007-06-16 12:25:22 +00:00
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match the real user ID or the save set-user-ID of the target process.
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2013-02-03 05:19:05 +00:00
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.PP
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The scheduling policy and parameters are in fact per-thread
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attributes on Linux.
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The value returned from a call to
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.BR gettid (2)
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can be passed in the argument
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.IR pid .
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Specifying
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.I pid
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as 0 will operate on the attribute for the calling thread,
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and passing the value returned from a call to
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.BR getpid (2)
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will operate on the attribute for the main thread of the thread group.
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(If you are using the POSIX threads API, then use
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.BR pthread_setschedparam (3),
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.BR pthread_getschedparam (3),
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and
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.BR pthread_setschedprio (3),
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instead of the
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.BR sched_* (2)
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system calls.)
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2007-07-20 13:35:31 +00:00
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.PP
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Originally, Standard Linux was intended as a general-purpose operating
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system being able to handle background processes, interactive
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applications, and less demanding real-time applications (applications that
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need to usually meet timing deadlines).
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Although the Linux kernel 2.6
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allowed for kernel preemption and the newly introduced O(1) scheduler
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ensures that the time needed to schedule is fixed and deterministic
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irrespective of the number of active tasks, true real-time computing
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was not possible up to kernel version 2.6.17.
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.SS Real-time features in the mainline Linux kernel
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2007-10-15 18:05:23 +00:00
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.\" FIXME . Probably this text will need some minor tweaking
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2008-09-05 06:11:29 +00:00
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.\" by about the time of 2.6.30; ask Carsten Emde about this then.
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Changes.old, clone.2, execve.2, fcntl.2, futex.2, getitimer.2, getpriority.2, mmap.2, mount.2, mprotect.2, sched_setscheduler.2, select_tut.2, setuid.2, sigaltstack.2, vfork.2, div.3, fenv.3, fmod.3, memchr.3, pthread_attr_setstackaddr.3, pthread_attr_setstacksize.3, pthread_getattr_np.3, queue.3, scanf.3, trunc.3, st.4, proc.5, services.5, utmp.5, bootparam.7, capabilities.7, feature_test_macros.7, futex.7, glob.7, man.7, netlink.7, unicode.7: Switch to American usage: "-wards" ==> "-ward"
American English uses "afterward" in preference to "afterwards",
and so on
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-09-26 05:34:47 +00:00
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From kernel version 2.6.18 onward, however, Linux is gradually
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2007-07-20 13:35:31 +00:00
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becoming equipped with real-time capabilities,
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most of which are derived from the former
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2008-03-19 13:23:18 +00:00
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.I realtime-preempt
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2008-09-05 06:11:29 +00:00
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patches developed by Ingo Molnar, Thomas Gleixner,
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Steven Rostedt, and others.
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2007-08-27 08:02:09 +00:00
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Until the patches have been completely merged into the
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2007-07-20 13:35:31 +00:00
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mainline kernel
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2008-11-06 19:10:03 +00:00
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(this is expected to be around kernel version 2.6.30),
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2008-05-14 06:46:09 +00:00
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they must be installed to achieve the best real-time performance.
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2007-07-20 13:35:31 +00:00
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These patches are named:
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2007-12-19 06:57:44 +00:00
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.in +4n
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2007-07-20 13:35:31 +00:00
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.nf
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2007-06-16 12:25:22 +00:00
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2007-07-20 13:35:31 +00:00
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patch-\fIkernelversion\fP-rt\fIpatchversion\fP
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.fi
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.in
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2004-11-03 13:51:07 +00:00
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.PP
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2007-07-20 13:35:31 +00:00
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and can be downloaded from
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capget.2, futex.2, sched_setscheduler.2, spu_create.2, spu_run.2, vfork.2, getnameinfo.3, netlink.3, cciss.4, console_codes.4, dsp56k.4, hpsa.4, sk98lin.4, filesystems.5, protocols.5, aio.7, capabilities.7, charsets.7, feature_test_macros.7, futex.7, hier.7, iso_8859-16.7, iso_8859-2.7, koi8-r.7, libc.7, man.7, netlink.7, numa.7, standards.7, unicode.7, units.7, uri.7, x25.7: Global fix: use UR macro where applicable
The syntax .UR http://example.com paired with .UE will create
links which one can interact, if the pager allows that. One
way to see the effect is ask the man(1) command to use browser
display, e.g.:
man -H man7/uri.7
("\:" is optional groff syntax to permit hyphenless line breaks.)
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-08-13 08:02:36 +00:00
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.UR http://www.kernel.org\:/pub\:/linux\:/kernel\:/projects\:/rt/
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.UE .
|
2007-07-20 13:35:31 +00:00
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Without the patches and prior to their full inclusion into the mainline
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kernel, the kernel configuration offers only the three preemption classes
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.BR CONFIG_PREEMPT_NONE ,
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.BR CONFIG_PREEMPT_VOLUNTARY ,
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and
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2007-09-20 16:26:31 +00:00
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.B CONFIG_PREEMPT_DESKTOP
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2007-07-20 13:35:31 +00:00
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which respectively provide no, some, and considerable
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reduction of the worst-case scheduling latency.
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With the patches applied or after their full inclusion into the mainline
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kernel, the additional configuration item
|
2007-09-20 16:26:31 +00:00
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|
.B CONFIG_PREEMPT_RT
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2007-07-20 13:35:31 +00:00
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becomes available.
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If this is selected, Linux is transformed into a regular
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real-time operating system.
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The FIFO and RR scheduling policies that can be selected using
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.BR sched_setscheduler ()
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are then used to run a process
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|
with true real-time priority and a minimum worst-case scheduling latency.
|
2007-11-19 04:24:28 +00:00
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|
|
.SH BUGS
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POSIX says that on success,
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|
|
.BR sched_setscheduler ()
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should return the previous scheduling policy.
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|
Linux
|
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.BR sched_setscheduler ()
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does not conform to this requirement,
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since it always returns 0 on success.
|
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH SEE ALSO
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sched_get_priority_max.2, sched_setparam.2, sched_setaffinity.2, sched_setscheduler.2, timer_create.2, malloc.3, pthread_attr_init.3, pthread_attr_setinheritsched.3, pthread_attr_setschedparam.3, pthread_attr_setschedpolicy.3, pthread_attr_setscope.3, pthread_attr_setstack.3, pthread_getattr_np.3, pthread_cancel.3, pthread_create.3, pthread_setschedparam.3, pthread_setschedprio.3, aio.7, time.7: Global ffix: disable justification and hyphenation in SEE ALSO
For a better visual result, disable justification and hyphenation
in SEE ALSO where page names are long.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-09-25 04:34:17 +00:00
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.ad l
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.nh
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2013-02-11 23:37:09 +00:00
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.BR chrt (1),
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2004-11-03 13:51:07 +00:00
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.BR getpriority (2),
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.BR mlock (2),
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.BR mlockall (2),
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.BR munlock (2),
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.BR munlockall (2),
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.BR nice (2),
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.BR sched_get_priority_max (2),
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.BR sched_get_priority_min (2),
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.BR sched_getaffinity (2),
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.BR sched_getparam (2),
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.BR sched_rr_get_interval (2),
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.BR sched_setaffinity (2),
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.BR sched_setparam (2),
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.BR sched_yield (2),
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.BR setpriority (2),
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2008-06-17 08:32:41 +00:00
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.BR capabilities (7),
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.BR cpuset (7)
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sched_get_priority_max.2, sched_setparam.2, sched_setaffinity.2, sched_setscheduler.2, timer_create.2, malloc.3, pthread_attr_init.3, pthread_attr_setinheritsched.3, pthread_attr_setschedparam.3, pthread_attr_setschedpolicy.3, pthread_attr_setscope.3, pthread_attr_setstack.3, pthread_getattr_np.3, pthread_cancel.3, pthread_create.3, pthread_setschedparam.3, pthread_setschedprio.3, aio.7, time.7: Global ffix: disable justification and hyphenation in SEE ALSO
For a better visual result, disable justification and hyphenation
in SEE ALSO where page names are long.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-09-25 04:34:17 +00:00
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.ad j
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2004-11-03 13:51:07 +00:00
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.PP
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.I Programming for the real world \- POSIX.4
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arch_prctl.2, fcntl.2, flock.2, get_robust_list.2, getpriority.2, ioprio_set.2, migrate_pages.2, mmap.2, mremap.2, msync.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, socket.2, subpage_prot.2, unshare.2, btree.3, dbopen.3, dl_iterate_phdr.3, dlopen.3, getnameinfo.3, hash.3, lockf.3, netlink.3, recno.3, rpc.3, xdr.3, cciss.4, console_ioctl.4, hpsa.4, initrd.4, msr.4, rtc.4, st.4, hosts.5, services.5, tzfile.5, aio.7, arp.7, capabilities.7, cpuset.7, feature_test_macros.7, futex.7, inotify.7, ip.7, ipv6.7, iso_8859-16.7, iso_8859-2.7, koi8-r.7, math_error.7, netlink.7, packet.7, pthreads.7, raw.7, spufs.7, udplite.7, uri.7, x25.7: Global fix: Various consistency fixes for SEE ALSO
Coauthored-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-09-24 07:53:22 +00:00
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by Bill O. Gallmeister, O'Reilly & Associates, Inc., ISBN 1-56592-074-0.
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2008-06-16 11:11:10 +00:00
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.PP
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.I Documentation/scheduler/sched-rt-group.txt
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arch_prctl.2, fcntl.2, flock.2, get_robust_list.2, getpriority.2, ioprio_set.2, migrate_pages.2, mmap.2, mremap.2, msync.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, socket.2, subpage_prot.2, unshare.2, btree.3, dbopen.3, dl_iterate_phdr.3, dlopen.3, getnameinfo.3, hash.3, lockf.3, netlink.3, recno.3, rpc.3, xdr.3, cciss.4, console_ioctl.4, hpsa.4, initrd.4, msr.4, rtc.4, st.4, hosts.5, services.5, tzfile.5, aio.7, arp.7, capabilities.7, cpuset.7, feature_test_macros.7, futex.7, inotify.7, ip.7, ipv6.7, iso_8859-16.7, iso_8859-2.7, koi8-r.7, math_error.7, netlink.7, packet.7, pthreads.7, raw.7, spufs.7, udplite.7, uri.7, x25.7: Global fix: Various consistency fixes for SEE ALSO
Coauthored-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-09-24 07:53:22 +00:00
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in the Linux kernel source tree
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2008-06-16 11:11:10 +00:00
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(since kernel 2.6.25).
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