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Date: Sun, 29 Mar 2009 22:03:14 -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:
>> David Xu wrote:
>>> David Xu wrote:
>>>> Julian Elischer wrote:
>>>>
>>>>> depends on the hardware.
>>>>> anyhow I was only saying it was possible, not necessarily
>>>>> good or even useful.
>>>>>
>>>>>
>>>>
>>>> I had done some works for thread private page shared by kernel
>>>> and userland when I was doing userland spinlock, if userland asks
>>>> a page, kernel will allocate it and put some interesting thing in
>>>> it by scheduler etcs, these code may be useful.
>>>>
>>> FYI:
>>> http://people.freebsd.org/~davidxu/schedctl/
>>
>> reading this quickly, you allocate a separately addressed page for
>> each thread, but,  how do you use it?
>>
>>
> I store the address in userland TLS area, then get it when I want to
> check some scheduling informations.

and the scheduler writes out interesting information to that
location?...