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Date: Sun,  4 Nov 2012 11:14:13 -0500
From: Martin Harriss <martin@Princeton.EDU>
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Subject: Re: [9fans] Kernel panic when allocating a huge memory
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On 11/03/2012 02:48 PM, Charles Forsyth wrote:
> local paging algorithms can avoid thrashing: "the process pages against
> itself".
> global paging algorithms typically do not (invariably do not, in my
> experience, but most people use essentially the same one, so there might
> be some that worked).
>
> Wilkes has a nice discussion of paging algorithms as an application of
> control theory
> in "The Dynamics of Paging".
> http://comjnl.oxfordjournals.org/content/16/1/4.short
>
> "It is notorious that the use of apparently innocuous scheduling and
> paging algorithms can give rise to the type of unstable behaviour known
> as thrashing."


Charles,

Regarding local paging algorithms, perhaps at this juncture you should
give yourself a pat on the back and post a pointer to the work you did
applying the EMAS-style paging behaviour to Unix.

(The EMAS papers are a joy to read, even 40 years on.  I'd dig up a
reference but here on the east coast of the US I'm in my 6th day without
power and have other things to worry about right now.)

Martin