Re: [mp1 and mp2] Grokking memory

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On Thu, 2005-02-10 at 19:33 -0500, Richard F. Rebel wrote:
> Does this report or help illustrate shared COW pages between apache
> processes?

I certainly though it did, but this work was done by my friend Doug
Steinwand, not by me.  I don't really know much more about it, but it
always seemed to work properly for me.

> I thought that particular part of /proc/<pid>/statm reported
> the pages potentially shared with other processes as they are part of
> dynamically loaded libraries.

I'm not sure the OS makes a distinction in reporting these things.

> When I check top, the SHARE column says 2328, which is exactly 4 (page
> size) x the 'share' number column number from top.  From what I
> understand so far, this does not represent COW pages shared between
> related processes.

It doesn't?  We tell people that it does in the mod_perl docs.

> Do I have the wrong end of the stick here?  (Id rather I did, because I
> have been using GTop to test my stuff before releasing).

Does GTop tell you something different?  I would expect it to give the
same answer.

- Perrin