min_free_kbytes documentation, /proc/sys/vm docs

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From: Pavel Machek
Date: Monday, August 13, 2007 - 6:46 am

Hi!

min_free_kbytes documentation says:

min_free_kbytes:

This is used to force the Linux VM to keep a minimum number 
of kilobytes free.  The VM uses this number to compute a pages_min
value for each lowmem zone in the system.  Each lowmem zone gets 
a number of reserved free pages based proportionally on its size.

...which is not too helpful :-(. In particular, should kernel survive
setting this to 0 and still work reliably? IOW is this
performance-only tweak, or does it correctness implications?

I guess it should also say something like "do not set this to more
than half of your physical RAM (or half of lowmem?) or you get an
instant OOM".

Plus, lowmem_reserve_ratio seems to be undocumented.
									Pavel
			(trying to come up with agressive settings, so
			that swap over ata over ethernet finally breaks).
			
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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Messages in current thread:
min_free_kbytes documentation, /proc/sys/vm docs, Pavel Machek, (Mon Aug 13, 6:46 am)
Re: min_free_kbytes documentation, /proc/sys/vm docs, Peter Zijlstra, (Mon Aug 13, 6:53 am)
Re: min_free_kbytes documentation, /proc/sys/vm docs, Pavel Machek, (Mon Aug 13, 7:12 am)