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Date: Mon, 5 Apr 2010 23:54:06 +0200
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH 00 of 41] Transparent Hugepage Support #17
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* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> there is just a _small handful_ of 2MB pages. Seriously. On a machine with 8 
> GB of RAM, and three quarters of it free, and there is just a couple of 
> contiguous 2MB regions. Note, that's _MB_, not GB.
>
> And don't tell me that these things are easy to fix. Don't tell me that the 
> current VM is quite clean and can be harmlessly extended to deal with this 
> all. Just don't. Not when we currently have a totally unexplained regression 
> in the VM from the last scalability thing we did.

I think those are very real worries.

The only point i wanted to make is that the numbers are real as well and go 
beyond what i saw characterised in the first email.

(It might still not be enough to tip the scale in the direction of 'we really 
want to do this' though.)

Thanks,

	Ingo

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