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Date: Mon, 30 Mar 2009 13:05:35 +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:
> 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?...
> 
> 
Yes.