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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Robert Watson <rwatson@FreeBSD.org>
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Date: Fri, 04 Jan 2008 13:48:36 +0100
In-Reply-To: <20080104113426.T77222@fledge.watson.org> (Robert Watson's
	message of "Fri\, 4 Jan 2008 11\:38\:23 +0000 \(GMT\)")
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Cc: freebsd-current@freebsd.org, Jason Evans <jasone@freebsd.org>,
	Igor Mozolevsky <igor@hybrid-lab.co.uk>
Subject: Re: sbrk(2) broken
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Robert Watson <rwatson@FreeBSD.org> writes:
> As I mentioned in my e-mail, it would be nice if our file system
> supported a way to reserve blocks for files without hooking them up to
> the file's visiible address space (in order to avoid zeroing them,
> which is required if you do want to hook them up for an unprivileged
> process).  However, that feature doesn't currently exist.

Even for files which are intended to be filled up immediately, telling
the file system ahead of time how much data will be written would allow
it to make much better layout decisions.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no