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Cc: John-Mark Gurney <gurney_j@resnet.uoregon.edu>, 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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>
> How would you see a sched_lock decomposition (and, if it is possible,
> how many locks it could be decomposed in?)

Rather than having a per thread lock, Solaris uses the lock for the
current container that a thread is associated with (cpu, run queue,
sleep queue, etc.) to serialize thread updates. I think this is probably
the best approach. A per proess spin lock would not scale well for large
multi-threaded apps.

				-Kip