mfaktc: a CUDA program for Mersenne prefactoring

[chalsall]

Originally Posted by James Heinrich

I've thrown together a rough chart of CUDA GPU performance comparison: http://mersenne-aries.sili.net/mfaktc.php

Sweet!

[kladner]

To James Heinrich:

Phenom II 1090T, 3.5GHz, core locked to mfaktc
Gigabyte GTX 460 (factory OC 715MHz, tested at chipset stock 675)
Prime95-64 on 4 other cores

mfaktc.ini settings:
NumStreams=3
CPUStreams=3
GridSize=3
AllowSleep=1

Factor=N/A,54168349,70,71

k_min = 10897430345340
k_max = 21794860698401

candidates=590.87M
time=4.449-5.176 (mostly upper mid 4.4xx)
rate=~131M/s
SievePrimes=5000 (occasional brief upticks)
avg. wait=~185 (with occasional swings as high as 1300. Most in the upper 180s)

Usage ~78% (narrow fluctuation, occasional dips to 67%)
vRAM usage 204-158=46MB
no factor for M54168349 from 2^70 to 2^71 [mfaktc 0.17-Win barrett79_mul32]
tf(): total time spent:  1h 13m 31.064s

[James Heinrich]

Originally Posted by kladner

Gigabyte GTX 460 (factory OC 715MHz, tested at chipset stock 675)
Factor=N/A,54168349,70,71
Usage ~78% (narrow fluctuation, occasional dips to 67%)
tf(): total time spent: 1h 13m 31.064s

Perfect, thanks. The above is the 4 pieces of info I need.

This is exactly why I need more data points:
8800GT: 13.90 GFLOPS per GHz-day/day
GTX 460: 8.18 GFLOPS per GHz-day/day


edit: Hmm, kladner -- which GPU is your GTX 460 using? GF104 or GF114? (if you're not sure, something like GPU-Z will tell you).

[kladner]

Originally Posted by James Heinrich

Perfect, thanks. ...........

edit: Hmm, kladner -- which GPU is your GTX 460 using? GF104 or GF114? (if you're not sure, something like GPU-Z will tell you).

This card is a Rev. 1, so it's a GF104 (confirmed by GPU-Z).

You're welcome! I'm glad to contribute to the effort. Do you want numbers for OC?

[James Heinrich]

OC numbers aren't neccesary, but if you feel like it, sure.
But I'm most interested in results from other GPUs, both older and newer.

[KyleAskine]

Originally Posted by James Heinrich

OC numbers aren't neccesary, but if you feel like it, sure.
But I'm most interested in results from other GPUs, both older and newer.

Want mfakto numbers too? Or just nVidia?

[James Heinrich]

Right now my data only has NVIDIA cards in there, but send me mfakto numbers and I'll wrangle some AMD data too.

[kladner]

Originally Posted by kladner

This card is a Rev. 1, so it's a GF104 (confirmed by GPU-Z).

I should have stated that this is a 1GB of RAM card.

[Jaxon]

For James, I got these results last night:

NVIDIA Geforce GTX 260 Core 216 running at default 576MHz
GPU GT200, Revision B1

Usage ~93%
Factor=N/A,52937323,70,72
no factor for M52937323 from 2^70 to 2^71 [mfaktc 0.17-Win 71bit_mul24]
tf(): total time spent:  2h  7m 47.851s
no factor for M52937323 from 2^71 to 2^72 [mfaktc 0.17-Win barrett79_mul32]
tf(): total time spent:  4h 25m 40.860s

[Dubslow]

Speaking of OC's and overclocking...
My two previous posts, complaining about 50% and 80% throughput I can now partially explain. My GTX 460 default core clock is 751 MHz (so I guess it is factory OC'ed, based on what kladner said) and in Windows I run it at 850 MHz. (I don't know of any Linux OC utility). So that explains why it's running at '80%' compared to what I was getting in Windows. I still can't explain entirely why it goes down to 50% Windows throughput, but I have figured out it has something to do with MPrime affinities (even though they should be independent of each other).

@James: With SievePrimes=5000, I get 180+/-2 M/s avg. rate at 850 MHz, and 160+/-2 M/s avg. rate at 751 MHz. I can't verify via GPUZ ATM because Linux.

[James Heinrich]

Originally Posted by Dubslow

@James: With SievePrimes=5000, I get 180+/-2 M/s avg. rate at 850 MHz, and 160+/-2 M/s avg. rate at 751 MHz. I can't verify via GPUZ ATM because Linux.

Thanks, but I need precise numbers running a single instance (just like kladner provided): GPU, assignment, GPU usage, runtime. If I'm missing any datum it's not much use to me.