mfaktc: a CUDA program for Mersenne prefactoring

[ET_]

Originally Posted by ET_

I have CC 1.3 and CUDA 4.1: should I update to 4.2 to get that 9% increase of speed?

I guess I could figure it myself just trying, but maybe I'm not the one in this situation...

Luigi

Yup, it seems so...

[flashjh]

Originally Posted by aketilander

Well I tried and installed the new version over the old. No, the old checkpoint file does not seem to be compatible with the new version of the program<snip>

This is no surprise :

Originally Posted by TheJudger

As usual: finish your current assignment and upgrade to mfaktc 0.19 after that. The upgrade is recommended to everyone because a speed improvement is possible on all GPUs.

Oliver

[flashjh]

Originally Posted by kladner

...I'm trying a minimum of 3000 now.)!

Do you have the resources to run another instance? With SP dropping so low, your GPU can handle more throughput if your CPU can handle it.

[kladner]

Originally Posted by flashjh

Do you have the resources to run another instance? With SP dropping so low, your GPU can handle more throughput if your CPU can handle it.

I'm afraid I really don't, unless I cut P-1 down to one worker. On the bright side, my combined average rate for four instances has gone from a low of about 420 M/s (NumStreams=3, factory OC, and Priority=Low, CPU stock) in 0.18, to around 480 M/s in 0.19. If I put it to NumStreams=5 and run at Normal priority it has hit 540-550 M/s.

It will take a few more completions to see what throughput works up to.

Interestingly, the driver version I got working (devdriver_4.2_winvista-win7_64_301.32_general.exe) seems to only allow the GTX 460 and 570 to run at their Factory OC clocks, 715Mhz and 780Mhz respectively.

[Chuck]

Originally Posted by Chuck

Super, I am running two instances on a GTX 580 and each has increased from 168 M/s to 202 M/s with sieveprimes 2000.

I see I should be looking at the time per class instead of this rate; however, the time per class is still lowest with sieveprimes 2000 (12.021s for M57xxxxxx)

[Chuck]

Originally Posted by Chuck

I see I should be looking at the time per class instead of this rate; however, the time per class is still lowest with sieveprimes 2000 (12.021s for M57xxxxxx)

Here are the worker windows.

[ckdo]

Would anyone be so kind to provide an mfaktc-0.19 binary for a glibc-2.11.1 linux64 system, or a version of libc-2.14.so which actually works under Ubuntu 10.04?

I've had no luck building my own and getting mfaktc-0.18 to work again was hard enough...

[Dubslow]

Originally Posted by ckdo

Would anyone be so kind to provide an mfaktc-0.19 binary for a glibc-2.11.1 linux64 system, or a version of libc-2.14.so which actually works under Ubuntu 10.04?

I've had no luck building my own and getting mfaktc-0.18 to work again was hard enough...

Will this do?

bill@Gravemind:~∰∂ /lib/x86_64-linux-gnu/libc-2.13.so
GNU C Library (Ubuntu EGLIBC 2.13-0ubuntu13.1) stable release version 2.13, by Roland McGrath et al.
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Compiled by GNU CC version 4.5.2.
Compiled on a Linux 2.6.38 system on 2012-03-06.
Available extensions:
	crypt add-on version 2.1 by Michael Glad and others
	GNU Libidn by Simon Josefsson
	Native POSIX Threads Library by Ulrich Drepper et al
	BIND-8.2.3-T5B
libc ABIs: UNIQUE IFUNC
For bug reporting instructions, please see:
<http://www.debian.org/Bugs/>.

Edit: Compilation attached. Warning: CUDA toolkit is version 4.1, so this code won't run with Kepler GPUs. (I can recompile with 4.2 if necessary.) Edit2: Reading your post in more detail, I'm not actually sure this will work... though I can post the libc-2.13.so if you want.

[ckdo]

Dubslow's binary actually works once supplied with a v4.1 libcudart, even with the v2.11.1 glibc.

Thanks a bunch, Bill.

[TObject]

I switched my GTX 580 to mfaktc-0.19. I can now load the GPU to 97% with three mfaktc threads where I needed four in version 0.18.

Thank you very much.

Edit: the M/s on each of the three threads is about 157.

[James Heinrich]

Originally Posted by TObject

the M/s on each of the three threads is about 157.

If you care to fiddle with mfaktc.ini::ProgressFormat a bit, GHz-days/day (%g) is probably more useful to look at than M/s (%r). This is the number you really want to maximize.

edit: Oh, wait, the new default config line does have %g in there.