1) At the moment the GPU version for HCC1 is the only GPU app in the pipeline. Some of the future research projects that are in the very early stages of the pipeline have the possibility of being GPU capable, but those are sometime in the future. As far as we see in all current and future projects, we will be running CPU versions. There may come a time where a research wants to run an app that was written only for opencl, but that time has not yet arrived. If we can compile it for CPU then we will run CPU. If it is written for GPU, then we will run it on GPU. However, it must be stated clearly that we do not develop the research applications. The researchers do and it is up to them to re-write the applications to take advantage of GPU processing.

2) We are definitely getting close to releasing GPU for HCC1. We already accept that the error rate for GPU will simply be higher than it is for CPU. When we release it, we will also be announcing that GPU is very different that CPU. Running a CPU app is supported by decades of work on operating systems that allow for process prioritization and sophisticated resource sharing. GPU's do not have the benefit of any of that capability. As a result, depending on how you use your computer, the power of the graphics card you have and what you use it for, you may experience an impact in your use of your computer if you run GPU. That is why GPU will be opt-in and even when you opt in the default behavior will be to only run while you are not using your computer. Having said this, the fact that a HCC1 workunit runs significantly faster on a GPU makes it worthwhile. We will leave decision to run or not run up to you.

3) The project selection screen needs to be redesigned. The requests from users to have the following features is understood by us:

a) Have tiers of projects preferences (i.e. give me beta or dddt2 if available, otherwise give me anything else except for hpf2 or cep2)
b) Give me hcc1 only in gpu but give me faah only in cpu
c) [let me know if I'm missing another capability here]

However, this flexibility is not present in either the BOINC server code or in our user interface so we need to do some work here. The addition of the 'don't run cpu' was something that was already present in the BOINC server code so we could get part way to the requested capability now and the rest of the way later.

Thanks for the detailed response, Kevin. It clears up a lot of questions on the approach to GPU.
I must say I harken back to the UD to BOINC conversion where decisions made at that time are still having limiting implications that continue to linger today (e.g. the silly “dog year” points system and the like). I hope WCG does not paint itself into a corner in the future by the GPU decisions they make today. Thanks again for the information.
@skgiven: Thanks for the input. The phrase “hop up the mountain backwards” did literally make me laugh out loud. I never heard that one before.

It is not true. E.g. look at PG settings:
http://www.primegrid.com/prefs.php?subset=project

For each "location":
Use CPU: yes/no
Use ATI GPU: yes/no
Use NVIDIA GPU: yes/no

For each subproject in each "location":
CPU: yes/no
CUDA: yes/no
AMD (ATI): yes/no

Hacked servers? Hmm... no kidding.

Look at other projects with applications for the GPUs:
http://setiweb.ssl.berkeley.edu/beta/prefs.php?subset=project
http://setiathome.berkeley.edu/prefs.php?subset=project
http://boinc.fzk.de/poem/prefs.php?subset=project
http://moowrap.net/prefs.php?subset=project
http://milkyway.cs.rpi.edu/milkyway/prefs.php?subset=project
http://www.gpugrid.net/prefs.php?subset=project
http://einstein.phys.uwm.edu/prefs.php?subset=project
http://donateathome.org/prefs.php?subset=project
http://boinc.freerainbowtables.com/distrrtgen/prefs.php?subset=project
http://boinc.thesonntags.com/collatz/prefs.php?subset=project
http://albert.phys.uwm.edu/prefs.php?subset=project
All have the settings for CPU/ ATI GPU/ NVIDIA GPU.
I participate in crunching on the GPUs from 3 years, then do not tell me that boinc is not ready for GPU!

In WCG we look forward to the application on the GPUs for almost a year. This is really a shame. Shame for IBM. In the area of GPUs "The Big Blue" may be called "The Small Weak Blue" - it's a shame!

Look at "Collatz Conjecture", this is only one-man stuff...
http://boinc.thesonntags.com/collatz/apps.php
... applications for:
- cuda23
- cuda31
- ati cal
- opencl amd
- opencl nvidia
... for Intel on MS, for AMD on MS, for Linux on AMD&Intel, for MacOS.

One-man stuff can, but IBM can not.

So lets see again at GPUGrid:

Use NVIDIA GPU
Enforced by version 6.10+ yes
Run test applications?
This helps us develop applications, but may cause jobs to fail on your computer yes
Is it OK for GPUGRID and your team (if any) to email you? yes
Should GPUGRID show your computers on its web site? yes
Default computer location ---
Maximum CPU % for graphics
0 ... 100 3
Run only the selected applications (all applications)
If no work for selected applications is available, accept work from other applications? yes
Use Graphics Processing Unit (GPU) if available yes
Use Central Processing Unit (CPU) yes

And a look at Primegrid:

Use CPU
Enforced by version 6.10+ no
Use ATI GPU
Enforced by version 6.10+ yes
Use NVIDIA GPU
Enforced by version 6.10+ yes

And Albert specific preferences:

Resource share
Determines the proportion of your computer's resources allocated to this project. Example: if you participate in two BOINC projects with resource shares of 100 and 200, the first will get 1/3 of your resources and the second will get 2/3. 100
Use CPU
Enforced by version 6.10+ yes
Use ATI GPU
Enforced by version 6.10+ yes
Use NVIDIA GPU
Enforced by version 6.10+ yes
Is it OK for Albert@Home and your team (if any) to email you? yes
Should Albert@Home show your computers on its web site? yes
Default computer location ---
Graphics setting: frames per second (FPS)
Warning: affects CPU consumption! Default value: 20 20
Graphics setting: render quality
Warning: requires hardware 3D acceleration! Default value: low low
Graphics setting: window width (pixels)
Default value: 800 800
Graphics setting: window height (pixels)
Default value: 600 600
Run only the selected applications (all applications)
If no work for selected applications is available, accept work from other applications? yes
Run CPU versions of applications for which GPU versions are available yes
GPU utilization factor of BRP apps
DANGEROUS! Only touch this if you are absolutely sure of what you are doing!
Wrong setting might even damage your computer! Use solely on your own risk!
Min: 0.0 / Max: 1.0 / Default: 1.0 1

Where exactly is the "at science level" option, that knreed said was not there, pretty please? Notably, PG you can choose a science, but there do not seem to be an and and, and / or for CPU and GPU. As for Collatz/Albert, how many sciences have they got running? One? Then you pick GPU yes, CPU yes, and the server will determine which compile to send of the one science, so is my reading.

As for "I participate in crunching on the GPUs from 3 years, then do not tell me that boinc is not ready for GPU!", where did I say "BOINC" was not ready for GPU processing? It is, just not in the desired granularity.

Maybe a true expert on GPU crunching can point me to a project preferences page that:

A) Has *multiple* sciences that run on GPU and CPU resources
B) And allow to pick as what is being asked for.

Sampling 3 DCs, not convinced seeing anything that resembles FAAH CPU Yes, FAAH GPU no, HCC CPU no, HCC GPU yes, when these sciences are available for both resources.

edit: spell.