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Date: Sat, 29 Oct 2005 00:29:10 -0700
From: Maxim Sobolev <sobomax@portaone.com>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Cc: Pertti Kosunen <pertti.kosunen@pp.nic.fi>,
	Robert Watson <rwatson@FreeBSD.ORG>, David Xu <davidxu@FreeBSD.ORG>,
	"Yuriy N. Shkandybin" <jura@networks.ru>, current@FreeBSD.ORG
Subject: Re: Timers and timing, was: MySQL Performance 6.0rc1
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Poul-Henning Kamp wrote:
> In message <4362BA38.1090603@portaone.com>, Maxim Sobolev writes:
> 
> 
>>You can solve most of those issues by exporting from kernel to userland 
>>not only page(s) with actual data, but also page(s) with code to handle 
>>that data. Then you can turn syscalls implementation in libc into plain 
>>function calls to addresses in that code page(s). This approach can 
>>potentially have other interesting applications, for example it will be 
>>possible to use processor-specific syscalls instructions without 
>>recompiling userland, move some of the ABI code into userland (i.e. 
>>freebsd32 layer on amd64) etc.
> 
> 
> I'm not sure I see much difference between a shared library and this
> solution, but I'm equally sure we'd love to se a prototype before
> we judge it :-)

Difference is that you won't have additional problems with userland and 
kernel versions mismatch and don't need any additional complexity 
associated with versioning/fallback logic.

-Maxim