[QUOTE=flashjh;327204]From output.c:

[CODE]if(mystuff->stats.class_time > 250)[/CODE]

So it looks like anything over 250 seconds will output an ETA[/QUOTE]

I see. Thanks again for your quick reply!

I just had an instance of mfaktc printing the ETA for an assignment that is too short for one. The figure isn't even correct because an assignment in this range (81.95M from 67 to 68 bits) consistently takes 3 minutes and 26 seconds on my GTX 555. I wonder if it's a bug.

[QUOTE=ixfd64;327240]I just had an instance of mfaktc printing the ETA for an assignment that is too short for one. The figure isn't even correct because an assignment in this range (81.95M from 67 to 68 bits) consistently takes 3 minutes and 26 seconds on my GTX 555. I wonder if it's a bug.[/QUOTE]

If the assignment is that short (or for any assignment really), then the "sample size" for an ETA estimate, especially *right at the beginning* of an assignment, is very varied. It's well within probability that one of so many would have an unusually high ETA.

[QUOTE=kladner;323880]That's very good to know. Thanks! I'm running 310.70, but will upgrade.
[/QUOTE]

I´m still running 306.97. Checked the NVIDIA site for new versions but all I read about 310.90 was related to improvements on some games, which doesn´t really interest me. The point is: would installing 310.90 be worth the trouble as far as mfaktc goes? Does anybody have any hard figures on that?
Thx

I installed 310.90 last night and didn't notice any difference in mfactc. It idn't hurt and it was an easy upgrade so I figure maybe I got a free bugfix in there, but performance did not improve. It stayed at 431.8<x<432.68.

I have it running on 4 570s and 1 560. No issues. All overclocked.

Running mfaktc on GPU while CPU is busy with other stuff:
[LIST][*]Windows 7 64bit, Xeon W3690, GTX 470: when I start prime95 on all 6 CPU cores the throughput of mfaktc [B]increases[/B] by ~1GHz/day[*]Windows 7 64bit, Core i7 3770k, GTX 680: when I start prime95 on all 4 CPU cores the throughput of mfaktc [B]decreases[/B] by ~3-5GHz/day[*]Linux 64bit, Xeon E5-2650, K20: when I put some heavy load on all CPU cores the throughput of mfaktc [B]increases[/B] by ~1-2GHz/day[/LIST]
Ideas? Comments?

Oliver

P.S. my GTX 680 stopped working on sunday... :sad:

[QUOTE=TheJudger;329142]Ideas? Comments?[/QUOTE]

As [URL="http://en.wikipedia.org/wiki/Isaac_Asimov"]Isacc Asimov[/URL] said, "The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' (I found it!) but 'That's funny ...'".

[QUOTE=TheJudger;329142]Ideas? Comments?
[/QUOTE]
Just brainstorming...
1. Measurement error. With the CPU busy, your GPU measurements aren't as precise.
2. You are unwittingly running an app that uses CPU and a little GPU. When the CPU is busy due to Prime95, the witless app uses less GPU. (Perhaps something supplied by NVIDIA.)

I experience a drop of ~5GHz/Day when I start P95 on each machine.

Where did you get a K20? How does it perform with mfaktc?

Running a mfaktc GPU-sieving on a Quadro2000 + ancient Xeon 5140, I still get some benefit from running two instances (1-1.5%, which is ~1-1.5 GHzdays/day).

I assume the rather slow CPU leaves some "holes" in scheduling the GPU kernels that are filled by the other instance.

If prime95 runs on all cores including hyper-threaded ones, I'd expect to see similar "holes" due to the CPU scheduling granularity. Also it is quite likely that the mfaktc-code has to be fetched from memory for running the outer loop that schedules the GPU kernels - it probably has long expired from the CPU caches when a GPU kernel finishes.

On the other hand, if no prime95 is running, modern CPUs significantly lower their core clock on idle, and it takes a few micro-seconds to spin up again. So if you have a "spare" hyper-thread that issues the next kernel immediately, it may be even faster if the CPU was not allowed to go into power-save mode.

I think, depending on which effect is stronger, you'll see things change for better or worse ...

Maybe also for you, the sum of two mfaktc instances is more than a single one ...