Message-ID: <47508475.7000109@byu.net>
Date: Fri, 30 Nov 2007 14:45:25 -0700
From: Eric Blake <ebb9@byu.net>
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To: cygwin@cygwin.com, steve@kelker.net
Subject: Re: cp.exe chunk size
References: <14093712.post@talk.nabble.com>
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According to skelker on 11/30/2007 2:23 PM:
> Hi,
> Is there a reason that cp.exe uses 8KB chunk sizes to copy files?  This
> behavior leads to very fragmented files, especially when copying large
> files.

This has been brought up before, if you want to search the archives for
posix_fallocate.  The problem is not with cp.exe, but with the way that
the POSIX read/write functions are implemented on top of Windows system
calls in cygwin1.dll.  When cygwin 1.7.0 comes out, I will be
experimenting with using posix_fallocate to see if that can reduce the
fragmentation.  But in the meantime, you'll have to just live with it.

- --
Don't work too hard, make some time for fun as well!

Eric Blake             ebb9@byu.net
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