1 .\" Copyright (c) 2006 Xin LI
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34 .Cd "options SCHED_CORE"
39 is an experimental scheduler that provides a number of advanced scheduler
40 features not present in
42 the default system scheduler, nor
43 .Xr sched_ule 4 where it is forked off.
44 These features address SMP and interactivity and include:
46 .Bl -bullet -compact -offset indent
48 Nice value of timesharing processes is respected. Allocation of
49 timeslice and interaction detection algorithm are based on
52 Per-cpu scheduling queue and load balancing.
56 Some cpu affinity code in wakeup path.
58 Support for POSIX SCHED_FIFO and SCHED_RR.
61 The following sysctls are relevant to the operation of
63 .Bl -tag -width indent
64 .It Va kern.sched.name
65 This read-only sysctl reports the name of the active scheduler.
66 .It Va kern.sched.imbalance_pct
67 (SMP specific) Lower watermark that triggers thread migration
68 if the difference is above this percentage.
69 .It Va kern.sched.imbalance_pct2
70 (SMP specific) Higher watermark where the current CPU is not
71 considered the preferred one for migration.
77 is not enabled by default as it is experimental.
85 scheduler first appeared in
89 .Aq davidxu@FreeBSD.org