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Date: Mon, 12 Apr 2010 09:56:20 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: hugepages will matter more in the future
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On Mon, 12 Apr 2010, Linus Torvalds wrote:
> 
> So as I already commented to Andrew, the code has no comments about the 
> "big picture", and the largest comment I found was about a totally 
> _trivial_ issue about replacing the hugepage by first clearing the entry, 
> then flushing the tlb, and then filling it.

Btw, this is the same complaint I had about the anon_vma code. There was 
no overview comments, and some of my fixes to that came directly from 
writing a big-picture "what should happen" flow chart, and either noticing 
that the code didn't do what it should have done, or that even the big 
picture was not clear.

And yes, I do realize that historically we (I) haven't been good at those 
things. It's just that the VM has gotten _so_ complicated that we damn 
well need them, at least when we add new features that the rest of the VM 
team doesn't know by rote.

			Linus

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