The LispOS Project: a position paper, part 2

[Dwight Hughes]

| From: Alaric B. Williams <alaric@abwillms.demon.co.uk>
| 
| > |From: Peter VanEynde
| > | I was thinking of this. It _can_ be done with a minimal kernel
| > module and | mmap. But I've got philosophical problems: if you want
| > to collect the | garbage in memory, you need to know what memory is
| > referenced by the | swapped out memory. And how can you know that
| > without swapping it in, or | keeping an expensive "pointers from
| > outer space" list? But I know only a | little about GC, so can
| > someone enlighten me?
| > 
| 
| IIRC the benefit comes from generational GC; don't swap out the youngest
| generation. Or something like that.

This is not quite sufficient, as explainted by this from Scott Burson:
>>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.<<

-- Dwight