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From: Kip Macy <kmacy@fsmware.com>
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Cc: Attilio Rao <attilio@freebsd.org>, freebsd-current@freebsd.org,
	David Xu <davidxu@freebsd.org>, Ivan Voras <ivoras@fer.hr>
Subject: Re: [PATCH] MAXCPU alterable in kernel config - needs testers
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> Wouldn't having a single run queue lock still serialize the cpu's when
> getting a thread to run?  Don't we really need a per cpu run queue, and
> then have a scheduler that puts threads on the cpu's run queues?

Balancing run queues has overhead as well. From what I've seen having
threads bouncing back and forth between the sleep queue and the run
queue because sleep / wakeup is overused (see lockmgr) is a bigger deal
right now. Moving to multiple run queues is inappropriate at this time.


					-Kip