Re: An idea for prefetching swapped memory...

[Chris Friesen <cfriesen@nortelnetworks.com>]

Helge Hafting wrote:
> Thomas Schlichter wrote:
> 
>> What I wanted to say is that if there is free memory it should be 
>> filled with
>> the pages that were in use before the memory got rare. And these are 
>> the pages
>> swapped out last. 

> "What we're going to need soon" is the best.  It isn't always predictable,
> but sometimes.  "The block following the last we read from some 
> file/fs-structure"
> is often a good one though.

With the current setup though, the memory is wasted.  It makes sense that we 
should fill the memory up with *something* that is likely to be useful.

If I have mozilla open, start a kernel compile, and then come back half an hour 
later, I would like to see the mozilla pages speculatively loaded back into memory.

Since the system is otherwise idle, it doesn't cost anything to do this.  I 
think its obvious that it is beneficial to swap in something, the only trick is 
getting a decent heuristic as to what it should be.

Chris



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Chris Friesen                    | MailStop: 043/33/F10
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