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Message boards : Graphics cards (GPUs) : Credit Drop ???

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Message 10376 - Posted: 2 Jun 2009 | 14:20:00 UTC

Has something changed that I missed, my Credit has dropped by about 40,000 - 50,000 Per Day & I don't know why. I haven't pulled any Box's or GPU Cards from the Project so I don't see why there's a drop unless the Credit's been reduced or the WU Length's have Increased without an Increase in Credit for the Extra Length of them ???

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Message 10379 - Posted: 2 Jun 2009 | 15:41:46 UTC

Yes to both. It's been happening for a while. Most of the 4933 credit WUs are now taking about 15% longer and the new style WUs are longer for the credit they offer. Maybe the admins are trying to slowly migrate the credit level downward.

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Message 10397 - Posted: 2 Jun 2009 | 22:23:49 UTC

I also noticed it. I think my observation of this behavior started after the workaround to fix the crashing WU on G92. Maybe this workaround slows down the speed of crunching.

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Message 10399 - Posted: 3 Jun 2009 | 0:01:07 UTC

Well that really Blows, the Project raises the Credits & then they take it all away with longer WU's without an appropriate increase in the Credits for the longer run times so you end up with negative credits than what you started with before they raised the Credit ...

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Message 10406 - Posted: 3 Jun 2009 | 5:33:20 UTC

I am not sure that this is happening ... when I look at my daily numbers they go up and down by large values on a day to day basis. As much as 50K a day.

It could be as simple as they don't run up the numbers for the stat sites in a way that smooths out the bumps in the ride. WIthout looking I would not hazard a guess as to all the reasons ... but 50K swings is quite a few tasks and I know my productivity is not such that this is simply a matter of *MY* timing of returning results.

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Message 10408 - Posted: 3 Jun 2009 | 7:15:25 UTC - in response to Message 10406.

On the work side, we have changed nothing. WU lengths are the same.
And definitely NO slow migration to a credit downward AT ALL.

Could you point to those WUs longer than usual?

Thanks,
ignasi

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Message 10415 - Posted: 3 Jun 2009 | 17:49:34 UTC - in response to Message 10406.
Last modified: 3 Jun 2009 | 18:05:53 UTC

I am not sure that this is happening ... when I look at my daily numbers they go up and down by large values on a day to day basis. As much as 50K a day.

Looking at your stats really won't tell you much. You need to look at the times for individual WUs of the same type. The one's I looked at first were the 4933 credit WUs since they've been around for a while.

Could you point to those WUs longer than usual?

Here's a 3 WU progression from the same card (GTX 280), newest WU first:

http://www.gpugrid.net/result.php?resultid=758769
# Time per step: 41.076 ms
# Approximate elapsed time for entire WU: 25672.281 s

http://www.gpugrid.net/result.php?resultid=749319
# Time per step: 36.258 ms
# Approximate elapsed time for entire WU: 22661.031 s

http://www.gpugrid.net/result.php?resultid=697460
# Time per step: 31.691 ms
# Approximate elapsed time for entire WU: 19806.688 s


Two from a different model card (GTX 260), newer WU first:

http://www.gpugrid.net/result.php?resultid=760959
# Time per step: 39.979 ms
# Approximate elapsed time for entire WU: 24987.075 s

http://www.gpugrid.net/result.php?resultid=702017
# Time per step: 34.888 ms
# Approximate elapsed time for entire WU: 21804.719 s


And here's my GTX 260, 2 newer WUs first, then 3 older ones:

http://www.gpugrid.net/result.php?resultid=763638
# Time per step: 39.926 ms
# Approximate elapsed time for entire WU: 24953.672 s

http://www.gpugrid.net/result.php?resultid=752559
# Time per step: 40.061 ms
# Approximate elapsed time for entire WU: 25038.250 s

http://www.gpugrid.net/result.php?resultid=737000
# Time per step: 34.814 ms
# Approximate elapsed time for entire WU: 21759.031 s

http://www.gpugrid.net/result.php?resultid=708495
# Time per step: 34.804 ms
# Approximate elapsed time for entire WU: 21752.812 s

http://www.gpugrid.net/result.php?resultid=691991
# Time per step: 34.744 ms
# Approximate elapsed time for entire WU: 21715.016 s


Finally, here's my oldest card (9600GSO, and a smaller percentage difference), again newer WU first:

http://www.gpugrid.net/result.php?resultid=755949
# Time per step: 95.027 ms
# Approximate elapsed time for entire WU: 59392.160 s

http://www.gpugrid.net/result.php?resultid=693698
# Time per step: 89.431 ms
# Approximate elapsed time for entire WU: 55894.359 s

Just a few examples (all examples above are the 4933 credit WUs), you can see this trend on pretty much any client. The newer type WUs also show the lower credit in line with the above time increase/credit as far as I can see. Perhaps it was the change to fix the failures on the older cards (as mentioned above by Nowi)?

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Message 10429 - Posted: 5 Jun 2009 | 13:50:12 UTC - in response to Message 10415.

The slight credit drops is probably caused by the fact that we had to use larger grid dimension in the PME method to avoid the cudafft bug when dimensions are not multiple of 32.

We are looking at improving this.

gdf

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Message 10430 - Posted: 5 Jun 2009 | 14:24:48 UTC

Thanks gdf, the info is appreciated. WUs have been running much more smoothly on older cards since the change :-)

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Message boards : Graphics cards (GPUs) : Credit Drop ???

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