Re: process selection

[Rik van Riel <riel@nl.linux.org>]

On Mon, 14 Jun 1999, Benjamin C.R. LaHaise wrote:

> I'm starting to think that going back and benchmarking my vm
> patches against 2.1.47 or 66 might prove useful as they used a
> physical page scanning with the old LFU technique,

I don't think this will be worth the effort. Firstly, physical
scanning is disastrous for effective I/O clustering (once we
hit swap, disk seek is _far_ more important than CPU time) and
LFU just isn't as good as LRU.

If you want a real improvement, you should port over some of
the (very nice) FreeBSD algorithms for I/O clustering and
assorted stuff.

As for including the sleep time in VMA selection. I think we
should just give an added 'bonus' if the process to which the
VMA belongs has been sleeping for a long time. If it's been
sleeping for a very long time (> 15 minutes) and the VMA is
not shared, we might even consider swapping the whole thing
out in one (physically contiguous for easy reading) swoop.


regards,

Rik -- Open Source: you deserve to be in control of your data.
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