Hi,
At 06:35 AM 7/24/2001 +0100, Daran wrote:
>As far as I can tell, both first time and DC LLs do P-1 factoring, but not
>trial factoring. (I suspect they will trial factor first if the exponant
>has not already been trial factored far enough, but I don't recall
>encountering this.)
Both will do trial factoring if necessary. It is pretty rare that a DC
needs more trial factoring.
>if the historical error rate for P-1s is the same as for LLs,
>(which is a reasonable assumption, given that they use the same FFT code*),
>then the probability of a second P-1 (using the same bounds) finding a
>factor that a first misses will be about 1% of this, i.e 0.02-0.05%, and
>only a single DC would be saved. Clearly not economical.
You are correct. Since P-1 factoring was introduced over a year ago, I'm
sure there have been quite a few needless P-1 runs. This happens primarily
on triple-checks and first-time tests that were abandoned after the P-1
run completed.
On the plus side, double-checking has still not reached the point where
first-time checking was when P-1 factoring was released.
> > Saying all that doesn't mean we couldn't break out work into more work
> >unit types, it would just mean we'd also have to have a factoring DC work
> >unit type if it was to be removed from the LL runs.
I'll see if I can work out a solution with Scott. A minimum solution would
have
the server return whether or not the exponent has already had P-1 factoring
done. A better solution would include giving CPU credit for P-1
factoring and making it a separate work type.
I'll keep y'all posted.
Best regards,
George
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