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Date: Sat, 28 Mar 2009 22:20:35 -0700
From: Julian Elischer <julian@elischer.org>
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To: David Xu <davidxu@freebsd.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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David Xu wrote:
> 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

depends on the hardware.
anyhow I was only saying it was possible, not necessarily
good or even useful.