Re: why swap at all?

From: Bernd Eckenfels
Date: Mon May 31 2004 - 18:31:39 EST


In article <40BBB5F7.1010407@xxxxxxxxxxxx> you wrote:
> Well, at the "expense" of paging out unused memory. I don't see
> any swapin.

On a slow system with small memory you quite often see swapped out
applications like for example a kopete messenger windows. Once you click on
it, it takes 10sec or more to get responsive again. Of course its a slow
system, but gradually paging out and forgetting image pages has that effecct
on faster systems too, makes the desktop sluggish.

> Well yes, but if I had another 57MB of physical memory then I would
> still turn on swap so that other 57MB of unused memory isn't wasted.

Actually the number of totally unused memory is quite small. Therefore the
pages get swapped in sooner or later anyway. And even if you turn of fswap
completely, the image pages backed up by binaries on disk get still freeded,
if the code is unused. So on my multimedia system I prefer to have no swap
(1GB ram) and make sure the pages are not freeded so aggressivley to keep
the system smooth and responsive (and allow spin down of the disk).

Bernd
--
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Project Freefire - http://www.freefire.org/
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