I've queued that polynomial up at nfs@home (sieving 20M..100M with 15e should get 400M relations easily)

[URL="http://mersenneforum.org/showthread.php?p=422876#post422876"]I finished the post processing[/URL], though someone else both submitted the factors to the FDB before I could and found the P33 in the next line before I. Control of the sequence has been wrested from me :smile:

I've run 7500@43e6 and 1800@110e6 on the C187.

How about you continue at 110e6 and I'll start on 260e6?

Ok, I'll run some more curves @110e6.

[QUOTE=unconnected;423502]Ok, I'll run some more curves @110e6.[/QUOTE]
+2200@110e6, total count 4000@110e6.

[QUOTE=unconnected;423502]Ok, I'll run some more curves @110e6.[/QUOTE]

Since this post (a couple hours short of 10 days) I've run 2928 curves at 260e6 (and continuing, for now). That's just over 1900 hyperthread hours, or say 850 Sandy Bridge core hours. I'm not sure how close unconnected is to finishing the t55, but lets assume it's complete, then as according to [URL="http://www.mersenneforum.org/showthread.php?p=416442#post416442"]fivemack's post[/URL], there's around a 1 in 11 chance of finding a factor, so we should do say 1/12 of the expected GNFS time as ECM at 260e6 (since it takes a non-trivial amount of work to get to t55 too).

I'm not sure how my thread hours relate to his thread hours, though. Does it seem reasonable that if GNFS175 is 20K thread hours, then GNFS187 is around 80-100K?

More like 100-120k. However, the 1/11 chance applies for ECM from an already-complete t55 to a complete t60. It's not the case that one should run 1/11th of the expected GNFS time, rather that one should compare whether a t60 will take less than 1/11th of expected sieve + LA time.

If we include LA time, 120k thread-hours is likely on the low end. Perhaps half a t60 is enough? That would be around 1/19 chance of a factor after t55, as half a t60 is around t58. If that would take ~6k thread-hours, then the 0.31*size heuristic fits well with expected-factor-effort estimates.

I'm mostly just wondering what fivemack's thread hours are, vs my SNB cores/hyperthreads. Once we can compare those we can likely come up with a reasonable ECM plan.

My grasp of his estimates is that one opteron-thread-hour is about the same amount of work as one HT-thread-hour on a typical 3.x ghz desktop intel chip.

HT is around 20% more efficient for sieve work, so at 3.4 ghz HT would effectively provide a 2ghz core, roughly the same as his opterons.

Okay, so after accounting for pauses, lets say it took 1850 thread hours to do 2928 curves at 260e6. If we assume the GNFS will be around 100K thread hours, and t55->t60 has around 1/11th chance to find a factor, then by fivemack's rule of thumb we should do ~9K thread hours of ECM at the t60 level, which is around 2928*9000/1850 = 14244 curves at 260e6. Does that seem reasonable?