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$FreeBSD: head/share/man/man4/sched_ule.4 170312 2007-06-05 01:10:47Z delphij $
.Dd June 5, 2007 .Os .Dt SCHED_ULE 4 .Sh NAME .Nm sched_ule .Nd ULE scheduler .Sh SYNOPSIS .Cd "options SCHED_ULE" .Sh DESCRIPTION The .Nm scheduler is an experimental scheduler that provides a number of advanced scheduler features not present in .Xr sched_4bsd 4 , the default system scheduler. These features address SMP and interactivity and include:
p l -bullet -compact -offset indent t Thread CPU affinity. t CPU topology awareness, including for hyper-threading. t Per-CPU run queues. t Interactivity heuristics that detect interactive applications and schedules them preferentially under high load. .El
p The following sysctls are relevant to the operation of .Nm : l -tag -width indent t Va kern.sched.name This read-only sysctl reports the name of the active scheduler. .El
p The .Nm scheduler is disabled by default as it is experimental. See the .Sx BUGS section for more information. .Sh SEE ALSO .Xr sched_4bsd 4 , .Xr sysctl 8 .Sh HISTORY The .Nm scheduler first appeared in .Fx 5.1 . .Sh AUTHORS .An Jeff Roberson .Aq jeff@FreeBSD.org .Sh BUGS As an experimental scheduler, .Nm is not enabled by default due to a number of known issues, including weak performance with several known workloads, and reports of instability. Deployment of .Nm in production environments is not recommended at this time.