From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yoann Padioleau <pad@fb.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Date: Sun, 22 Jun 2014 01:10:57 +0000
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Subject: Re: [9fans] [GSOC] plan9 kernel scheduler
Topicbox-Message-UUID: fc5554fa-ead8-11e9-9d60-3106f5b1d025

if you look in sys/src/9/port
and grep for functions like

sched()
schedinit()
runproc()
updatecpu()
repriotirize()

you'll get the logic of the scheduling algorithm. It's mostly
priority queue fair robin I think, with a few hooks to prefer reschedule
on the same CPU.

Context switching is done with the
gotolabel()
setlabel()
mmuswtich()
taskswitch()


On Jun 21, 2014, at 12:30 PM, yan cui <ccuiyyan@gmail.com> wrote:

> Hi all,
>=20
>     On SMP or multicore systems, what algorithm(s) does Plan 9 use to sch=
edule(context switching and load balancing) different tasks (process or thr=
ead) and where is it implemented? I searched some plan9 documents, but cann=
ot find some about this topic. Any recommendations?   =20
>=20
>=20
> Thanks, Yan
>=20
> --=20
> Think big; Dream impossible; Make it happen. =20