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From: John Baldwin <jhb@freebsd.org>
To: Dag-Erling =?utf-8?q?Sm=C3=B8rgrav?= <des@des.no>
Date: Wed, 8 Oct 2008 17:01:44 -0400
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Cc: freebsd-hackers@freebsd.org, ushasri tummala <tummala.ushasri@gmail.com>
Subject: Re: What is the time between 2 mi_switches in freebsd.
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On Wednesday 08 October 2008 04:23:43 pm Dag-Erling Sm=C3=B8rgrav wrote:
> John Baldwin <jhb@freebsd.org> writes:
> > There isn't a fixed timeslice due to preemption for interrupts, etc. =20
However,=20
> > the default time slice is available as the kern.sched.quantum sysctl:
> >
> > % sysctl -d kern.sched.quantum
> > kern.sched.quantum: Roundrobin scheduling quantum in microseconds
>=20
> des@ds4 ~% uname -a
> FreeBSD ds4.des.no 8.0-CURRENT FreeBSD 8.0-CURRENT #48 r183493M: Tue Sep =
30=20
23:35:48 CEST 2008     des@ds4.des.no:/usr/obj/usr/src/sys/ds4  amd64
> des@ds4 ~% sysctl kern.sched.quantum
> sysctl: unknown oid 'kern.sched.quantum'

Apparently the quantum isn't exposed anywhere for ULE.

=2D-=20
John Baldwin