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Message-ID: <028f01c31e38$0e428c30$78d96f83@pomello>
From: "Max Bowsher" <maxb AT ukf DOT net>
To: <cygwin AT cygwin DOT com>
References: <Law10-F79o4cWScPAA600033a95 AT hotmail DOT com>
Subject: Re: SPARSE files considered harmful - please revert
Date: Mon, 19 May 2003 19:54:19 +0100
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John Vincent wrote:
>
> I looked up sparse files on MSDN and found the following link:
>
>
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/base/sparse_file_operations.asp
>
> The most interesting thing is that a sparse file is only sparse if the
zeros
> in the file are written with a special operation. I strongly suspect that
> the patch to support sparse files introduced in cygwin is incorrect (or at
> least incomplete)

Areas that are simply seeked over, and never written to, should be sparse as
well.

Anyway:

Based on the posted numbers, global use of sparse files is a bad idea. Can
we conditionalize sparse files on a $CYGWIN option? (Or something else, I
don't mind, but the important thing is that it should not be on by default.)



Max.


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