[VM] NCM performance report

Helge Horch Helge.Horch at munich.netsurf.de
Thu Mar 25 21:10:37 UTC 1999


At 22:14 24.03.99 -0800, Dan Ingalls wrote:
>The main reason I have balked at this change so far is the cost in space
>for small implementations. [...] At that point we would have added 180k
>to the 530k mini image.  This is why I am being conservative.

Thanks for the rationale. I had "paged out" this important limiting factor.

On the other hand, if such a speedup was reproducable on a PDA system, it
might still be worth considering NCM to squeeze out more sends/sec from the
processor. Depends on the specific hardware situation given.

>Since you have published the numbers (and since I am certainly curious
>about them), I have to ask if they represent an apples-to-apples comparison.
>Are the VMs generated from the same compiler,

Touché. I have to admit that I just *assumed* they were comparable.
Andreas' off-the-shelf VM was compiled by the current Visual-C++, correct?

>and are the only differences in the handling of methods?

I see that Tim jumped to my help with a full explanation. :)

>I know Tim has probably been frustrated at our apparent recalcitrance in
>not immediately adopting NCMs, so I'm glad you have induced me to articulate
>the issues.

I did not want to sound "demanding"- it's just that I was happy with the
results I got, wondered if others shared the same experience or what the
general reception was.

Dan, Tim, Ian- Thank you all for your explanations and clarifications.

Cheers,
Helge





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