Re: [patch][rfc] remove ZERO_PAGE?

[Linus Torvalds <torvalds@linux-foundation.org>]

On Sun, 29 Jul 2007, Linus Torvalds wrote:
> 
> I'd love to hear "here's a real-life load, and yes, the ZERO_PAGE logic 
> really does hurt more than it helps, it's time to remove it". At that 
> point I'll happily apply the patch.

Btw, in the absense of that, I'd at least like to hear an acknowledgement 
that the complexity isn't worth it, and that what used to work fine was 
broken because the reference counting overhead gets us on large-scale 
machines.

IOW, I certainly like removing lines of code. In that sense I _love_ that 
patch. I really just react negatively because I really think you first set 
ZERO_PAGE up to fail.

So even if you cannot find a load where this all matters, at least point 
to commit b5810039a54e5babf428e9a1e89fc1940fabff11 (or exactly whichever 
one it was that started ref-counting ZERO_PAGE) and blame *that* one, 
rather than blaming ZERO_PAGE for the problem.

It has served us well for fifteen years, we shouldn't blame it for 
problems that came from elsewhere.

			Linus

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