[Dovecot] Design: Asynchronous I/O for single/multi-dbox

[Steffen Kaiser]

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On Tue, 16 Mar 2010, Stan Hoeppner wrote:

> You didn't read the paste Jakob.  Or maybe you don't comprehend the
> material?  Also, it seems you're unaware that Dovecot creates at minimum 1
> imap process per client connection.  In the case of Thunderbird, it creates
> 5 imap processes.  Each one is over 2MB in size, and all of those imap
> processes share close to 2MB of memory pages that are identical, because the
> code is identical.  If they're all identical, why have 500 copies in memory
> instead of one?

The "paste" talks about data.
You talk about code.

If I display a process map of an active imap process, I have:
mapped: 2656K    writeable/private: 460K    shared: 300K
Essentially you are talking about 460KB of KSM-able data.

IMHO, all modern Unix-alike system just "map" code pages read-only into 
the process and share them among all processes. No KSM required at all.

Regards,

- -- 
Steffen Kaiser
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