The LispOS Project: a position paper, part 2

Tue, 3 Jun 1997 11:22:34 +0200 (MET DST)

On Tue, 3 Jun 1997, Scott L. Burson wrote:
> I agree: you're confused :-)
> First off, I *am* talking about *during* GC.  The only time the GC could cause
> a page fault is while it is running.
Hmm. And during allocation? If you just over-commit the OS will fault if
you want to use a "new" page. This will force some page out..

> Secondly, the age of a generation has nothing, in general, to do with how
> recently the pages of that generation have been referenced.  It has only to do
> with how many GC cycles the objects in the generation have survived.
That's why I wrote "oldest generation and not recently used".
Communication problem I fear.

> And thirdly, which I should have explained, I am really talking here about
> background collections of older generations.  We would like to be able to do
> these, as I say, without having them chew up all our real memory.  Young
> generations tend to be small enough that this isn't a problem anyway.
Aha. This sound a lot like the "GC in place" option of the later versions
of Genera. Right? (I've been reading the slug mailing archives)

Yes, I agree that this could help a lot, but IIRC it was a "special"
option even in Genera, so I'm not that convinced it will help. Especially
because we don't have full control about the memory management of the
system. (this of course could be a reason to convert people from "LispOS
on top of ..." to "LispOS in full control"...)

Groetjes, Peter

It's logic Jim, but not as we know it.
Look in keyservers for PGP key.
Version: 3.12
GS/CS/L/C d->? s+:++>+@ a-- C++(+++)>$ ULOS++>++++$ P+>++++ L+++>++++
E>++ W+(--) U++>+++ o>+ K? w--- O>+@ M-? V? PS++ PE(--) Y+ PGP+>++
t++>+++ 5++ X++>+++ R tv b+++>++++ DI++ D++@ G+>++ e++>++++ h!>+ r+ y+