Re: Plain 2.4.5 VM

[Rik van Riel <riel@conectiva.com.br>]

On Wed, 30 May 2001, Mark Hahn wrote:

> 	if (ptep_test_and_clear_young(pte))
> 		age up;
> 	else		
> 		get rid of it;
> 
> shouldn't we try to gain more information by scanning page tables
> at a good rate?  we don't have to blindly get rid of every page
> that isn't young (referenced since last scan) - we could base that
> on age.  admittedly, more scanning would eat some additional CPU,
> but then again, we currently shuffle pages among lists based on relatively
> sparse PAGE_ACCESSED info.
> 
> or am I missing something?  

The "getting rid of it" above consists of 2 parts:

1) moving the page to the active list, where
   refill_inactive_scan will age it
2) the page->age will be higher if the page
   has been accessed more often

regards,

Rik
--
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However, without VM there's truly nothing to lose...

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