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From Vick Khera <vi...@khera.org>
Subject Re: performance tuning - where does the slowness come from?
Date Tue, 04 May 2010 19:12:18 GMT
On Tue, May 4, 2010 at 2:57 PM, Ran Tavory <rantav@gmail.com> wrote:
> I'm also interested in a way to cap mmap so I can take advantage of it but
> not swap the host to death...
>

Isn't the point of mmap() to just directly access a file as if it were
memory?  I can see how it would fool the reporting tools into thinking
that much memory was in use since it is part of your virtual address
space, but I am not following why it would actually *use* more memory.

Perhaps it is overwhelming the buffer cache and that is pushing other
data pages out to swap?  Just  a wild-assed guess here.

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