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From: Linus Torvalds <torvalds@osdl.org>
Subject: Re: [RFC \ WISH] Add -o option to git-rev-list
Date: Mon, 11 Dec 2006 09:07:43 -0800 (PST)
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On Mon, 11 Dec 2006, Linus Torvalds wrote:
> 
> That's not timing what I asked. That's just timing the "git-rev-list". You 
> need to time the "cat" part too. Either use a script, or do something like 
> 
> 	time sh -c "git-rev-list ... | cat > /dev/null".

Btw, if you do this, you'll actually see one of the _real_ advantages of 
pipes.

On an SMP system, you'll easily get output like "110%CPU", since now the 
git-rev-list and the user can run in parallel. Of course, they can do so 
with temp-files too, but then you have all the "is it a true EOF, or is it 
just the fact that the writer hasn't written everything yet" problem (and 
the _normal_ solution for that is to simply not allow any overlapping 
work).