[DGD] alternate swapout pressure system

[Jared Maddox]

> Date: Sun, 22 Jul 2012 14:37:29 -0700
> From: Shentino <shentino at gmail.com>
> To: "All about Dworkin's Game Driver" <dgd at dworkin.nl>
> Subject: [DGD] alternate swapout pressure system
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> What if instead of basing swapout rate on the number of resident
> objects, I instead based it on dynamic memory load?
>
> like say, a soft limit below which nothing is swapped out at all, and
> then each task results in one object being swapped out per X amount of
> memory used over the soft limit?
>
> And also, perhaps a hard limit of "swapout until memory usage goes
> back down below this mark"
>
> I've done a bit of a prototype of this and it seems to work well so
> far, any thoughts on this?
>

> Date: Sun, 22 Jul 2012 16:39:50 -0700
> From: Shentino <shentino at gmail.com>
> To: "All about Dworkin's Game Driver" <dgd at dworkin.nl>
> Subject: Re: [DGD] alternate swapout pressure system
> Message-ID:
> 	<CAGDaZ_qj48ThLoLcD_34K6DMiucaq=y=mCgwXH41B9xoyVxDsw at mail.gmail.com>
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> One more thing.
>
> The hard memory cap idea is mostly intended to keep DGD from pissing
> off the OS if the mud grows too big.
>
> I figured that it's better for DGD to evict objects than for the OS to
> start paging, so the hard cap would proabably be proportional to total
> system RAM.
>

If I ever spend enough time on my GUI patch to get it working then I'm
planning to use it for a toy windowing system, so this definitely
interests me.

I don't think I ever looked very hard at the code that does this,
could the swapout tests be moved to a single function, so that any
other changes to them can be contained? I figure that making one call
for multiple tests should be easier to deal with than putting all of
the tests directly into the actual swapping code.