John M McIntosh <johnmci at smalltalkconsulting.com> said:
>a) In case of an issue you can't kill the VM, go back and restore 
>from a change set because changes you make *are* persistent.
>
Make backups ;-)? I'm fully aware that this may be an issue, and I don't
have a solution. Well, maybe one - some copy-on-write trickery but that'd
quickly get really OS-dependent.

>b) If your machine crashes I'm not quite sure what the state of your 
>image would be, are there pages outstanding to be written not yet 
>written?
>
That would need a sort of image checker. 

>c) If you wander around writing bits, how much IO would that 
>generate, especially if you do a full GC and compaction.
>
That's a real issue, especially if the image doesn't fit in physical RAM.
Probably the allocator and GC would need to be modified to apply some
heuristics so that objects that 'belong' together move 'closer' together (now,
just define these two terms ;)). 

OTOH, it doesn't seem like a very hard patch, and it would be fun to try it
out just for the heck of it. Can't do it myself, first have to build that
textsearching thingy for the mailing list...

-- 
Cees de Groot               http://www.cdegroot.com     <cg at cdegroot.com>
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