At 11:00 AM 10/12/99 -0400, you wrote:
>I'm okay with that. But I think, if possible, it'd be good to break up
>primes into like, 1 month chunks, & distribute them. I'm sure it'd be
>possible, I just don't know if/how much it'd impact speed.
Not possible. Well, POSSIBLE, but it would actually slow the effort down.
The problem is that the test you're performing uses the results of the last
"loop" to compute the next value. To make the math simpler, I won't use
the actual LL test, but something much simpler:
X = 0;
DO 32,722,124 times
X = X + 1;
Now, if you're running this prgram, forget for a moment that you and I can
easily look ahead and see that after a thousand times, X is
1000. Unfortunately, there's no "shortcut" in the Lucas-Lehmer test
whereby one can look ahead. You have to do this:
X = 0
Prior result was 0 so 0 + 1 = 1
Prior result was 1 so 1 + 1 = 2
Prior result was 2 so 2 + 1 = 3
Prior result was 3 so 3 + 1 = 4
Prior result was 4 so 4 + 1 = 5
Prior result was 5 so 5 + 1 = 6
etc.
Note that you cannot just "jump ahead" to the 120th loop, because you need
to know what the RESULT of the 119th loop was before you can start. And
you need the 118th loop to start the 119th, etc, all the way back to loop # 1.
If you're testing an exponent of 32,361,147 (for example), you *must* do
all 32,361,144 calculations, and they have to be done in order.
If you tried to "break them up", with, say, 100,000 "iterations" per user,
then the person with 100,001 through 200,000 cannot even start 100,001
until all 100,000 iterations of the last person had been finished.
If you tried this, you'd only slow things down, because you'd have to send
the "mid-test results" back to Entropia, and then out to the next tester,
before they can start. That's what would slow things down -- the
back-and-forth of the intermediate results.
Yes, it takes a while, but its very much best for one person to just do the
whole test, even though it's going to take two years.
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