Hi,
At 10:08 AM 3/29/2001 +1000, Steve Phipps wrote:
>For the exponents I'm looking at, I suspect that the FFT size is of
>order a kilobyte (BTW, can I look the FFT sizes and breakpoints up
>somewhere?) and so the minimum memory required is less than 1MB.
A size 1024 FFT can handle exponents up to 22599. For rough estimating
purposes, divide the exponent by 21 and round up to the next FFT size.
>However, I use mprime with the available memory set to 24MB and I've
>noticed that ECM uses almost all of this. I'd like to know why ECM is
>using so much memory - does it enable it to run faster?
Yes, more memory can be used to save some operations.
> And how much
>memory would ECM 'like' to use if it was available?
I've never studied this. I suspect you quickly reach the point
of diminishing returns. Try mprime with 8MB and I'll bet you'll
notice little difference.
Regards,
George
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