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diff --git a/schedutils/chrt.1 b/schedutils/chrt.1 new file mode 100644 index 0000000..b85717b --- /dev/null +++ b/schedutils/chrt.1 @@ -0,0 +1,158 @@ +.\" chrt(1) manpage +.\" +.\" Copyright (C) 2004 Robert Love +.\" +.\" This is free documentation; you can redistribute it and/or +.\" modify it under the terms of the GNU General Public License as +.\" published by the Free Software Foundation; either version 2 of +.\" the License. +.\" +.\" The GNU General Public License's references to "object code" +.\" and "executables" are to be interpreted as the output of any +.\" document formatting or typesetting system, including +.\" intermediate and printed output. +.\" +.\" This manual is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +.\" GNU General Public License for more details. +.\" +.\" You should have received a copy of the GNU General Public License along +.\" with this program; if not, write to the Free Software Foundation, Inc., +.\" 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +.\" +.\" 2002-05-11 Robert Love <rml@tech9.net> +.\" Initial version +.\" +.TH CHRT 1 "June 2010" "util-linux" "User Commands" +.SH NAME +chrt \- manipulate the real-time attributes of a process +.SH SYNOPSIS +.B chrt +.RI [ options ]\ prio +.IR command\ [ arg ]... +.br +.B chrt +.RI [ options ] +.B \-p +.RI [ prio ]\ pid +.SH DESCRIPTION +.PP +.B chrt +sets or retrieves the real-time scheduling attributes of an existing \fIpid\fR, +or runs \fIcommand\fR with the given attributes. Both policy (one of +.BR SCHED_OTHER , +.BR SCHED_FIFO , +.BR SCHED_RR , +.BR SCHED_BATCH , +or +.BR SCHED_IDLE ) +and priority can be set and retrieved. +.PP +The +.BR SCHED_BATCH +policy is supported since Linux 2.6.16. The +.BR SCHED_IDLE +policy is supported since Linux 2.6.23. +.PP +The +.BR SCHED_RESET_ON_FORK +flag for policies SCHED_RR and SCHED_FIFO is supported +since Linux 2.6.31. +.SH OPTIONS +.TP +.B -a, --all-tasks +Set or retrieve the scheduling attributes of all the tasks (threads) for a +given PID. +.TP +.B -b, --batch +Set scheduling policy to +.BR SCHED_BATCH +(Linux specific). +.TP +.B -f, --fifo +Set scheduling policy to +.BR SCHED_FIFO . +.TP +.B -i, --idle +Set scheduling policy to +.BR SCHED_IDLE +(Linux specific). +.TP +.B -m, --max +Show minimum and maximum valid priorities, then exit. +.TP +.B -o, --other +Set policy scheduling policy to +.BR SCHED_OTHER . +.TP +.B -p, --pid +Operate on an existing PID and do not launch a new task. +.TP +.B -r, --rr +Set scheduling policy to +.BR SCHED_RR +(the default). +.TP +.B -R, --reset-on-fork +Add +.B SCHED_RESET_ON_FORK +flag to the +.B SCHED_FIFO +or +.B SCHED_RR +scheduling policy (Linux specific). +.TP +.B -v, --verbose +Show status information. +.TP +.B -h, --help +Display usage information and exit. +.TP +.B -V, --version +Display version information and exit. +.SH USAGE +.TP +The default behavior is to run a new command: +.B chrt +.I prio +.IR command\ [ arguments ] +.TP +You can also retrieve the real-time attributes of an existing task: +.B chrt \-p +.I pid +.TP +Or set them: +.B chrt \-p +.I prio pid +.SH PERMISSIONS +A user must possess +.BR CAP_SYS_NICE +to change the scheduling attributes of a process. Any user can retrieve the +scheduling information. +.SH NOTES +Only +.BR SCHED_FIFO , +.BR SCHED_OTHER +and +.BR SCHED_RR +are part of POSIX 1003.1b Process Scheduling. The other scheduling attributes +may be ignored on some systems. +.SH AUTHOR +Written by Robert M. Love. +.SH COPYRIGHT +Copyright \(co 2004 Robert M. Love +.br +This is free software; see the source for copying conditions. There is NO +warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +.SH "SEE ALSO" +.BR taskset (1), +.BR nice (1), +.BR renice (1) +.sp +See +.BR sched_setscheduler (2) +for a description of the Linux scheduling scheme. +.SH AVAILABILITY +The chrt command is part of the util-linux package and is available from +ftp://ftp.kernel.org/pub/linux/utils/util-linux/. |