multiple heaps

Miguel Barreiro Paz <>
Mon Oct 16 20:23:22 CEST 2000

	Thanks for the answers. Summarizing,

> The separate heaps improve the soft real time characteristics of the
> emulator 
	Now, wouldn't a shared heap with more generations achieve the same
effect? - quoting Erik Johansson:

> We plan to implement a shared heap with several generations to test
> whether this is the case or not.

	so, we may eventually find out. Admittedly, it might be more

>  It seems that with modern microprocessors the cost to copy data
> between heaps is cheap, if the memory pages happens to be in the
> processor cache, 

	I suppose copying includes relocating list pointers here, so long
lists would have a bigger copy penalty than large monolithic chunks of
data - certainly, modern processors are likely to do an addition for
free, hidden in the access latency.

> For bulk data transfer You should pass binary objects instead, which
> are allocated in common storage off heap (if not smaller than 64 bytes

	Yes, thanks for the suggestion; This is however a bit of a hack -
converting a list to a binary and then into a list again is not the
cleanest and clearest way one might wish.

	By the way, what is the current size limit for the common binary
storage? (I seem to recall it was 64MB or so in R6A, which became a
problem here).



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