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Date: Thu, 27 May 2010 16:48:42 -0700
From: Dave Hayes <dave@jetcafe.org>
Subject: Locking a file backed mdconfig into memory
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On FreeBSD 7.3-STABLE I'm mounting a DVD and doing something like
this:
 
  mdconfig -a -t vnode -o reserve -o readonly -f /dvd/file

so that /dvd/file becomes the backing storage for my memory
disk. 

Now if the system is under severe memory pressure, will this
memory get swapped out, causing a read from the DVD? How would
I tell the system to never swap this file out of ram, even under
severe memory pressure?

The idea is to load this backing storage once and only once 
from the DVD into memory and leave it there. 

Thanks in advance.
-- 
Dave Hayes - Consultant - Altadena CA, USA - dave@jetcafe.org 
>>> The opinions expressed above are entirely my own <<<

Have you noticed how economical the human race is with it's
idols?  It sets them up, enjoys them, then falls upon them
and devours them until nothing is left. Even the complete
consumption of the idol, if it is another human being, is
not the end. There are then hundreds of years worth of
argument and analysis to be worked through...