Nathan Russell wrote:
>It will only get worse for the 486 users when PrimeNet begins
>handing out exponents that will need factoring to 65 bits. Of
>course, they can use factoroveride, but that's not helpful to
>the network as a whole.
However, the factoroverride switch is not designed for use with
the PrimeNet server. For reasons unknown, the server does not
release the exponent upon report of factoring being done when
using the switch. That's why there was a complaint a while back
on the list that somebody had several thousand factoring
assignments out.
>For those who don't know, due to CPU design reasons that I
>don't claim to understand, factoring to 65 bits takes easily
>four or five times as long as factoring to 64 bits. In
>version 19, it was set to take place for exponents 13.38M and
>up. I believe PrimeNet will reach this point in a few months.
While I had calculated it at 4.5 times as long (2x for the same
percentage completion, and 2.25x for the iteration time), I've
been getting ~4.2x as long. For some reason, IPS assigned me
a couple dozen exponents just above 13.38M, and what would
have normally taken me 38 hrs. for to 2^64, it's been taking
~160 hrs. to do to 2^65...
For comparison sakes, I'll note this: I've had my system set
up to output once every 60 secs (for 63- and 64-bit factors).
At this point it was getting a % complete of 0.132% every
~59.98 seconds for 2^64 (64-bit factors), and a % complete of
0.066% every ~136.20 seconds for 2^65 (65-bit factors).
Eric
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