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Date: Tue, 5 Jun 2012 21:03:34 +0200
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: Bruce Evans <brde@optusnet.com.au>
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Cc: Gianni <gianni@FreeBSD.org>, John Baldwin <jhb@FreeBSD.org>,
	Alan Cox <alc@rice.edu>, Alexander Kabaev <kan@FreeBSD.org>,
	Attilio Rao <attilio@FreeBSD.org>,
	Konstantin Belousov <kib@FreeBSD.org>, freebsd-arch@FreeBSD.org,
	Konstantin Belousov <kostikbel@gmail.com>,
	Dag-Erling Sm??rgrav <des@des.no>
Subject: Re: Fast vs slow syscalls (Re: Fwd: [RFC] Kernel shared variables)
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On Wed, Jun 06, 2012 at 04:36:54AM +1000, Bruce Evans wrote:
> On Tue, 5 Jun 2012, Luigi Rizzo wrote:
...
> >>Yes, we know getpid() is slow, I think the question is does it matter that
> >>it's slow in something other than a microbenchmark.  Can you name the
> >>application that you've seen use getpid()?
> >
> >i think the important question is, for any function X:
> >   Q1	"does it require horrible hacks or a huge amount of work
> >	to make X syscall-free ?"
> >rather than
> >   Q2	"does it matter to make X fast"
> 
> s/huge amount/any/
> 
> Work is all the programming work to implement it and maintain it forever.

well, some work has a return in term of fun, beauty, pride
so the balance is still favourable.

cheers
luigi