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Date: Tue, 13 Nov 2001 13:13:20 -0500
From: Christopher Faylor <cgf AT redhat DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: AW: cygwin vfork
Message-ID: <20011113181320.GA959@redhat.com>
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References: <000101c16c39$19f18980$651c440a AT BRAMSCHE> <3BF13F87 DOT 2070600 AT ece DOT gatech DOT edu>
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On Tue, Nov 13, 2001 at 10:43:03AM -0500, Charles Wilson wrote:
>> The VM comment is referring to the large footprint of XEmacs which means
>> that doing a fork requires copying an awful lot of data (and hence takes a
>> long time), most OS's do copy-on-write for vfork so the overhead is never
>> incurred.
>
>And of course, cgf chimed in on this thread, but I can't find his message 
>in my mail archive, and (as mentioned elsewhere) the cygwin ml archive is 
>missing his message as well, so I can't quote it here for you.

With vfork, there is very little copying going on.  Only cygwin's heap is
copied.

Of course, if you don't use vfork then cygwin's fork implementation *is*
pretty slow.

cgf

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