Hello,
Start situation : same host (46603). Same day of WU,always long run WUV9.22 cuda 80. I repeat again, on the same host.
One WU run 50,742 sec for credit of 181,050 (ratio : 3.56 cr/second)
A other run 32,598 sec credit : 110,400 (ratio : 3.38 cr / sec)
OK so fa it is more or less the same

A other run 24,129 sec credit : 63,750. Ratio : 2.64cr/sec

I repeat, I ompare three WU on the same host.
Between hot it can change. Here not it is the same host.



Can someone explain me the ratio difference ???
All my host are visible, als WU ???

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They are different apps. The short ones probably utilizes the GPU less efficiently.

Both BOINC and GPUGrid broke the equivalence between credits and processing power (GFlops) several years ago. Credit is now just a dimensionless number, enabling comparison between hosts and users within each separate project.

Here at GPUGrid, we went through a phase where there was a fairly high probability that tasks would fail mid-run. And tasks which fail get no credit at all.

The longer a task runs before failure, the greater the loss of potential credit. And the longer a task is planned to run, the higher the average loss per failed task. For that reason, the administrators here decided to grant a higher rate of credit per hour for longer running tasks, to provide some compensation for the observed failures.

Your figures illustrate perfectly - higher rate for longer tasks - that this policy still applies and is working as designed.

They are different apps. The short ones probably utilizes the GPU less efficiently.

Same apps, different tasks.

Hello,
Once again I repeat : I compare differents tasks from the same apps (long run...) on the same host (46603) !!!
I look the credits on my stat page here ongpugrid.

I NOT compare host/apps/...
Only same apps on same host
Waiting explanation, best regards

I am running 5 BOINC projects. Each of them has a different method for assigning credits. My only opinion is that the more they are the less they are worth, exactly like money.
Tullio

Hello,
Once again I repeat : I compare differents tasks from the same apps (long run...) on the same host (46603) !!!
I look the credits on my stat page here ongpugrid.

I NOT compare host/apps/...
Only same apps on same host
Waiting explanation, best regards

I repeat my answer. It is a deliberate policy applying to this project only.

I am running 5 BOINC projects. Each of them has a different method for assigning credits. My only opinion is that the more they are the less they are worth, exactly like money.
Tullio

Hello Tulio. Please read all !!!
For the third time, I repeat : same project, same app, same host, only the WU is different and coming from the same batch file !!!
Both credit calulated by GPUGrid

Both credit calculated by GPUGrid

Yes - but calculated by GPUGrid staff, not by the BOINC software.

Look at the three tasks you started this thread with.

ADRIA_FOLDADAH2: Credit 181,050.00
PABLO_2IDP: Credit 110,400.00
ADRIA_FOLDUCB: Credit 63,750.00

Each task type gets a fixed credit, but different task types get different credits - as I think you've said already. The staff decide that.

Hello,
Once again I repeat : I compare differents tasks from the same apps (long run...) on the same host (46603) !!!
I look the credits on my stat page here ongpugrid.

I NOT compare host/apps/...
Only same apps on same host
Waiting explanation, best regards

I repeat my answer. It is a deliberate policy applying to this project only.

@Richard.
In wich language I need to write ?
I repeat : same project (GPU), same host (46603), same Apps (long time...),
I know the credit change between projects.
I ompare what is possible.
To compare :
Take a car. You need to drive 100km.
The first time you drive at 100km/h, so one hour driving needed. Let us say 10 liters gasoline required.
The second time, you again, in the same car, also 100km on the same road. Sometime you drve faster (more gasoline needed), sometime slower (less gasoline needed). Nomally about the same as first race (let us says about 5% differences.
Then a third race, perfect the same conditions as the first. But you need 12 liters gasoline : 20% more


So why there is so big difference with the third race, same road, car, driver, weather,......? All is perfect the same !!!

@marsinph

I think I may have the final answer to this. I am honestly not sure how the GPU Work Unit credits are calculated, either by the staff or automatically based on total FLOPS. If it is the latter I think you will notice a lack of GPU usage on certain WUs. This directly affects the total WU time and therefore credit/second. Because the app sends all the data over the PCIe bus to the CPU for double precision compute, if you single threaded CPU speed is lacking or you have a less than optimal PCIe configuration, this can lead to low GPU usage.

If the WU is a very large number of molecules, very little CPU usage is required as compared to GPU usage and most likely your credit/second will be higher.

I am honestly not sure how the GPU Work Unit credits are calculated, either by the staff or automatically based on total FLOPS.

At this project - unusually - the credits are calculated by the staff.

Look at your total list of GPU tasks. The credit for every single one of them (he sticks his neck out, risking egg on face!) is an exact multiple of 50.00. The chances of that happening by floating point arithmetic, whether you're counting flops or microseconds, are minuscule.

I don't know how many molecules are in the GPU tasks but Toni wrote that the CPU tasks treat only one molecule. I have tried to understand in the "output" directory of stderr.txt what the program is doing but it is beyond my knowledge of computer chemistry. I only remember that SCF stands for Self Consistent Field and DFT for Density Functional Theory.
Tullio

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Here at GPUGrid the same app does very different simulations between different workunit batches (they are named differently).
The granted credits are set manually by the GPUGrid staff for every batch one by one based a short test run on their systems. This gives approximate results.
The lower the number of atoms, the utilization (~credit/time ratio) of faster GPUs will be lower.
All of the above together explains the different credits and the different credit/time ratio.
When you compare the credit/time ratio of different batches (done by the same app), you compare apples to oranges.
Look at the end of the stderr.txt output for clues:
ADRIA_FOLDADAH2
PABLO_2IDP
ADRIA_FOLDUCB

   name of       Granted   Number of     avg time     number of
    BATCH        Credits     steps       per step       atoms
ADRIA_FOLDADAH2: 181,050     12,50M       4.059ms      32,198
PABLO_2IDP:      110,400     10,00M       3.259ms      24,524
ADRIA_FOLDUCB:    63,750     12,26M       1.932ms      11,340

Maybe it's the same car,
but not the same road, not the same weather, not the same fuel, not the same driver, and not the same other cars in the road.
Hope that helps to understand this.

Something seems wrong with the credit calculation:

today, a WU did NOT get granted the "below 24 hours" extra bonus of 20%.
The total time from download till upload was 23 hours and 35 minutes. I received the 20% bonus for "below 48 hours", and that was it.
http://gpugrid.net/result.php?resultid=20416897

Okay, no big deal, but my efforts to make to make it below 24 hours, like giving it an extra GPU glock speed, were for nothing :-(

The total time from download till upload was 23 hours and 35 minutes.

According to the task you've linked it was 24 hours and 1 minute and 8 seconds:

    Sent: 25 Jan 2019  9:59:05 UTC
Received: 26 Jan 2019 10:00:13 UTC

The processing of the workunit took 84,544 seconds which is 23h 29m 04s.

I received the 20% bonus for "below 48 hours", and that was it.
http://gpugrid.net/result.php?resultid=20416897

Perhaps the download of the task and/or the upload of the result took more than normal. I see a couple of stalled uploads on my hosts lately, also the project's website can't be reached sometimes on my hosts. However if I try to reach it from a different ISP at the same time, there's no problem.

The total time from download till upload was 23 hours and 35 minutes. I received the 20% bonus for "below 48 hours", and that was it.
http://gpugrid.net/result.php?resultid=20416897

Okay, no big deal, but my efforts to make to make it below 24 hours, like giving it an extra GPU glock speed, were for nothing :-(

Unfortunately I ran into this literally hundreds of times when I was running 17 750ti GPUs. Due to some consideration by the Furies and other WU length Gods the 750Ti often just misses the 24 mark even when using a 0 project priority. Here's the WU time in question:

20416897 205584 25 Jan 2019 | 9:59:05 UTC 26 Jan 2019 | 10:00:13 UTC

You missed the 24hr bonus by 68 seconds. The time is calculated from when the WU download starts to when it is reported (not uploaded). Unfortunately downloads often stall numerous times even on fast connections (this has been going on forever on this project and only on this project AFAIK). Uploads take a while because they're huge. Yes, it's irritating if you're running 750Ti GPUs. I empathize with you.

I have downloaded a QC task on my main Linux box. It is there, waiting to run. No other task is running. Disk space is abundant.
Tullio

Zoltan wrote:

Perhaps the download of the task and/or the upload of the result took more than normal. I see a couple of stalled uploads on my hosts lately, also the project's website can't be reached sometimes on my hosts.

Although I experienced upload stalls several times before (and reported about them here), I didn't notice them in the recent past.
However, I am - of course - not present each time a WU of my total 5 hosts is being uploaded, so it could well have happened.
In fact, I couldn't imagine any other reason.

Hello, I have a similar problem (or rather anomaly) - my credit got quadrupled today from ~70k to ~280k. I noticed that I finished a long GPU task, but why is this one particular task worth so much? How to find out?

Edit: found it - http://www.gpugrid.net/result.php?resultid=20499467

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I am a software developer and I know absolutely nothing about medicine. So I want to help those, who do know :)

CPU: AMD Ryzen 5 1600
GPU: Nvidia GTX 1050Ti (upgrade to 1070 coming soon™)