Just attached to the project and wanted to make sure I'm where I'm supposed to be with configuration. I am just now getting going with GPU apps and wanted to find something to work on in Linux with my GTX 460. It looks like I am running the stock apps for N-Body and for CUDA. I have been reading in the forums quite a bit to familiarise myself with the current state of the apps. Am I correct in my understanding that there are no optimized N-body apps? Is there an optimized CUDA app? I am using a Linux 64bit OS? How long typically does it take for a result to validated? And there are no "wingmen" in MW@Home? I have been doing only Seti@Home so far and that is what I'm familiar with. I just want to make sure I am not returning bogus data. All my CUDA tasks seem to end up with a success state, that is all that have returned so far, but I was hoping to see some verification either from a wingman or the project.

On a personal note ...... I find the project goals very interesting because I can relate. I am an amateur astronomer and the questions about which tidal structures are within the galaxy and which are in the halo are very current considering the number of galaxies we have cannibalized over the aeons.

Cheers, Keith

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Welcome!

For the most part there are no wingmen. There are times when a quorum is required just to make sure your computer isn't going crazy. But it's the exception not the rule.

The server should automatically send out SSE2 optimized apps if your CPU supports it, there are SSE versions as well. Between that and the apps being updated nobody has done anything else with them that I know of yet at least.

Same goes for the OpenCL nVidia app. So everything that auto downloads is the best there is currently for Linux (That I know of at least).


Though to ask a question, what distro / driver version are you using? I tried the nVidia app with Ubuntu / distro distributed drivers the other day with pretty poor results. I had a lot of errors that didn't show up until the WU was done.

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Thanks for the welcome Astromancer. I am using Ubuntu 10.10 64bit with the Nvidia 260.19.06 driver. Yes, that is what I was concerned about ..... whether I was returning good data. I can't seem to find any tasks in the validated results table. How long do they hang around? I am now showing 2 results with "validation inconclusive" tags so am wondering? They are here:
http://milkyway.cs.rpi.edu/milkyway/workunit.php?wuid=225160813
http://milkyway.cs.rpi.edu/milkyway/workunit.php?wuid=225160809

Also, I seem to see total credits already racked up but without seeing anything accumulated in the Valid table. Also,when I look at the WU claimed credits, it is a really low value.... on the order of 0.08 or some such, yet the total credits on my account page shows almost 3,000 credits. Why the disparity?


Any answers? Cheers,

Keith

Also, I seem to see total credits already racked up but without seeing anything accumulated in the Valid table. Also,when I look at the WU claimed credits, it is a really low value.... on the order of 0.08 or some such, yet the total credits on my account page shows almost 3,000 credits. Why the disparity?

Any answers? Cheers,

Keith

Hi Keith,

You had a number of valid WUs but once validated they are quickly purged due to server issues. The claimed credit is based on CPU time but since the GPU apps use very little CPU the credit estimate means nothing. The GPUs can do these WUs up to 100 times faster than a CPU and the credit is awarded appropriately. Have fun on the project!

To elaborate on what Beyond said.

Every WU is worth a fixed ammt of credit, much like at SETI. SETI iirc removed the "Claimed Credit" from where you look at tasks, MW could do the same since it doesn't mean anything here.

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Thanks for the replies Beyond and Astromancer. Good to hear that I seem to be producing good data and that to not worry about results appearing in the valid tables. I also assume that the MW@Home credit algorithm is based primarily on the number of flops used to crunch the WU, much like Seti@Home? Doesn't matter whether they come from a GPU or CPU. I always wished I could do more than one project in the past, mainly to cover for the outages, but I never could because of my OS and hardware limitations. Now, with this brand new computer, I have many more choices. Should be fun!

Cheers, Keith

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