xref: /freebsd/share/man/man4/sched_ule.4 (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
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25.Dd August 10, 2012
26.Dt SCHED_ULE 4
27.Os
28.Sh NAME
29.Nm sched_ule
30.Nd ULE scheduler
31.Sh SYNOPSIS
32.Cd "options SCHED_ULE"
33.Sh DESCRIPTION
34The
35.Nm
36scheduler
37provides a number of advanced scheduler
38features not present in
39.Xr sched_4bsd 4 ,
40the traditional system scheduler.
41These features address SMP and interactivity and include:
42.Pp
43.Bl -bullet -compact -offset indent
44.It
45Thread CPU affinity.
46.It
47CPU topology awareness, including for hyper-threading.
48.It
49Per-CPU run queues.
50.It
51Interactivity heuristics that detect interactive applications and schedules
52them preferentially under high load.
53.El
54.Pp
55The following sysctls are relevant to the operation of
56.Nm :
57.Bl -tag -width indent
58.It Va kern.sched.name
59This read-only sysctl reports the name of the active scheduler.
60.It Va kern.sched.quantum
61This read-write sysctl reports or sets the length of the quantum (in
62micro-seconds) granted to a thread.
63.El
64.Sh SEE ALSO
65.Xr sched_4bsd 4 ,
66.Xr sysctl 8
67.Sh HISTORY
68The
69.Nm
70scheduler first appeared in
71.Fx 5.1 .
72.Sh AUTHORS
73.An Jeff Roberson Aq Mt jeff@FreeBSD.org
74