On Tue, 2 Mar 1999, Mike Pellegrino wrote:
> Neil,
>
> I have "finished" a beta virtual memory manager for the Palm which pages
> dynamic RAM to the disk. What this means is that you can allocate more
> RAM that physically available (I page it to storage RAM), but you can
> only lock down handles if there is enough dynamic RAM to hold what's in
> the handle. It may help you in your memory problems as far as storage
> size goes.
>
> The docs aren't written yet (been a busy week so far-although the params
> are identical to the Palm API calls) and I've not done enough stochastic
> testing of the manager yet. But I'm happy to entertain beta users if
> you're interested.
>
> The performance of VMMHandleNew sucks--it takes about 25-30 ms per
> allocation. This is tied almost directly to DmNewRecord performance.
> I'm currently investigating ways to improve this or amortize the cost
> over a number of VMM operations. Other operations take much less time.
Are you allocating underlying blocks in both the heap and storage during
VMMHandleNew, or is the new handle just going into storage (since it
starts out unlocked)? It sounds to me like it would probably (barring
information to the contrary) make more sense to start out with an unlocked
allocation on the heap, paging it out to storage only when heap fills up.
Heap would then act as a cache for as many of the blocks as reasonable &
possible, locked or unlocked, instead of only holding locked blocks.
It would be more work to do it that way, though. :-)
--
Kenneth Albanowski ([EMAIL PROTECTED], CIS: 70705,126)
