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Date: Sun, 29 Mar 2009 08:35:45 +0800
From: David Xu <davidxu@freebsd.org>
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To: Julian Elischer <julian@elischer.org>
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Cc: Scott Long <scottl@samsco.org>, Sergey Babkin <babkin@verizon.net>,
	freebsd-hackers@freebsd.org, attilio@freebsd.org,
	phk@phk.freebsd.dk, freebsd-current@freebsd.org, prashant.vaibhav@gmail.com
Subject: Re: Improving the kernel/i386
	timecounter	performance	(GSoC	proposal)
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Julian Elischer wrote:
> Scott Long wrote:
>> I've been talking about this for years.  All I need is help with the 
>> VM magic to create the page on fork.  I also want two pages, one global
>> for gettimeofday (and any other global data we can think of) and one
>> per-process for static data like getpid/getgid.
>
> interestingly it is even feasible to have a per-thread page..
> it requires that the scheduler change a page table entry tough.
>

I will knock his door at midnight if he added such a heavy weight
task in the scheduler, TLB shutdown is horrible, and big code size
squeezing out data from CPU cache is not idea model.
scheduler should be as simple as just a context switching routine.
:-)

David Xu