Re: [PATCH] vma limited swapin readahead

[Stephen C. Tweedie]

Hi,

On Thu, Feb 01, 2001 at 02:45:04PM -0200, Rik van Riel wrote:
> On Thu, 1 Feb 2001, Stephen C. Tweedie wrote:
> 
> But only when the extra pages we're reading in don't
> displace useful data from memory, making us fault in
> those other pages ... causing us to go to the disk
> again and do more readahead, which could potentially
> displace even more pages, etc...

Remember, it's a balance.  You can displace a few useful pages and
still win overall because the cost _per page_ goes way down due to
better disk IO utilisation.

> One solution could be to put (most of) the swapin readahead
> pages on the inactive_dirty list, so pressure by readahead
> on the resident pages is smaller and the not used readahead
> pages are reclaimed faster.

Yep, that would make much sense.

--Stephen