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Date:	Mon, 11 Nov 2002 11:09:45 -0500
From:	Christopher Faylor <cgf AT redhat DOT com>
To:	cygwin-developers AT cygwin DOT com
Subject:	Re: ntsec patch #4: passwd and group
Message-ID:	<20021111160945.GA16199@redhat.com>
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On Mon, Nov 11, 2002 at 02:56:12PM +0100, Corinna Vinschen wrote:
>On Fri, Nov 08, 2002 at 12:10:13PM -0500, Pierre A. Humblet wrote:
>> Corinna Vinschen wrote:
>> Can you elaborate? Why is it a problem to store them in the 
>> cygheap? 
>> I saw Chris' comments about slowing things down. That makes 
>> sense for programs that never stat or create a file with uid 
>> and gid different from the current user.
>> However when Chris was doing the test this caching mechanism
>> wasn't present yet, stating or creating any file would force
>> a passwd/group reread. So it's more surprising.
>
>AFAIR, Chris was surprised, too.  I don't know more details, though.

There is always a tradeoff between the overhead of ReadProcessMemory and
file I/O.  In this case, I guess file I/O from a file that was in cache
probably won.

cgf

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