I have added app_config.xml with the use all GPUs command and in the event log it doesn't say (not used) next to the 2nd GPU. Some projects on this computer use both GPUs and some only use 1. This is the strangest problem I've had in a while. Anyone have any idea how to fix this?

You need to make a cc_config.xml and place it in the boinc folder not the GPUGrid folder.

I'm sorry I meant cc_config.xml. I already have this set up and boinc doesn't say (not used), below that it also says use all coprocessors. I don't know what's going on here.

12/2/2017 8:22:45 PM | | CUDA: NVIDIA GPU 0: GeForce GTX 1080 Ti (driver version 388.13, CUDA version 9.1, compute capability 6.1, 4096MB, 3550MB available, 11974 GFLOPS peak)
12/2/2017 8:22:45 PM | | CUDA: NVIDIA GPU 1: GeForce GTX 1080 Ti (driver version 388.13, CUDA version 9.1, compute capability 6.1, 4096MB, 3550MB available, 11974 GFLOPS peak)
12/2/2017 8:22:45 PM | | OpenCL: NVIDIA GPU 0: GeForce GTX 1080 Ti (driver version 388.13, device version OpenCL 1.2 CUDA, 11264MB, 3550MB available, 11974 GFLOPS peak)
12/2/2017 8:22:45 PM | | OpenCL: NVIDIA GPU 1: GeForce GTX 1080 Ti (driver version 388.13, device version OpenCL 1.2 CUDA, 11264MB, 3550MB available, 11974 GFLOPS peak)
12/2/2017 8:22:45 PM | | Host name: DESKTOP-L0VCIE2
12/2/2017 8:22:45 PM | | Processor: 8 GenuineIntel Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz [Family 6 Model 94 Stepping 3]
12/2/2017 8:22:45 PM | | Processor features: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss htt tm pni ssse3 fma cx16 sse4_1 sse4_2 movebe popcnt aes f16c rdrandsyscall nx lm avx avx2 vmx tm2 pbe fsgsbase bmi1 hle smep bmi2
12/2/2017 8:22:45 PM | | OS: Microsoft Windows 10: Professional x64 Edition, (10.00.16299.00)
12/2/2017 8:22:45 PM | | Memory: 15.94 GB physical, 18.32 GB virtual
12/2/2017 8:22:45 PM | | Disk: 118.75 GB total, 93.87 GB free
12/2/2017 8:22:45 PM | | Local time is UTC -5 hours
12/2/2017 8:22:45 PM | | Config: use all coprocessors

When you installed the second card, did you remove the previous driver and do a clean install of the driver downloaded from the nvidia website? Sometimes, if you just add the card without reinstalling the driver, it will fail to use the second card. Something to try at least.

Edit..

Both cards are the same model type and vendor?

Both cards are the same model type and vendor?

Both cards are the same model type and vendor?

Yes they are the exact same card.

Are you running CPU WUs, if so try suspending them.

What are resource share on the other project which are CPU only WUs if you are running them?

In Boinc Manager, in advanced view, under options, computer preferences, computing tab, what are your usage limits?

Are you running CPU WUs, if so try suspending them.

What are resource share on the other project which are CPU only WUs if you are running them?

In Boinc Manager, in advanced view, under options, computer preferences, computing tab, what are your usage limits?

I think you found the problem. Previously I've had trouble running CPU WUs at the same time as a system with more than one GPU. For some reason even with "use at most 100% of the CPUs" and "use at most 100% of the CPU time" It still disables one GPU WU even with resource share of GPUgrid at 10000 and Drugdiscovery at 0. Anyone have any ideas of how to prioritize GPU WUs to always run no matter what?

Are you running CPU WUs, if so try suspending them.

What are resource share on the other project which are CPU only WUs if you are running them?

In Boinc Manager, in advanced view, under options, computer preferences, computing tab, what are your usage limits?

I think you found the problem. Previously I've had trouble running CPU WUs at the same time as a system with more than one GPU. For some reason even with "use at most 100% of the CPUs" and "use at most 100% of the CPU time" It still disables one GPU WU even with resource share of GPUgrid at 10000 and Drugdiscovery at 0. Anyone have any ideas of how to prioritize GPU WUs to always run no matter what?

If BOINC thinks that a task is at risk of missing its deadline, it will schedule it first (ie: prioritize it), even if it is a CPU task.

My suggestion: Find out which projects are giving your CPU tasks that end up in deadline risk high-priority mode. Then see if the deadlines are too short for them.

If the deadlines are reasonable, then perhaps your cache settings ("Store at least x days" and "Store up to an additional y days") are set way too high, such that you get a ton of work which BOINC thought you could make at the time, but the estimate wasn't perfect, and when it came time to run them they went into deadline risk high-priority mode.

My suggestion: Try cache settings of x = 0.8 days, and y = 0.5 days.

If BOINC thinks that a task is at risk of missing its deadline, it will schedule it first (ie: prioritize it), even if it is a CPU task.

It applies at all times.

As an example, let's say you have a GPU app that budgets (1 NVIDIA + 0.501 CPU) for each instance. Let's say you have 2 GPUs, and 8 CPUs, with plenty of tasks available, but the CPU ones all have immediate deadlines.

When the BOINC scheduler runs, it:
- Sees the "deadline miss" CPU tasks
- Schedules them first... 1, 2, 3, ..., 8.
- Allows "up to n+1 CPUs", for any GPU tasks... so, allows budgeting for up-to-9 CPUs.
- Will schedule *1* of your GPU tasks, bringing CPU budget up to 8.501
- Will NOT schedule the 2nd GPU, because that would put the budget to 9.002, which is over the 9.000 limit.

I have a few rigs with multiple GPUs, and also some settings like GPUGrid to run multiple tasks per GPU. So, this exact scenario comes up from time to time.

If CPU tasks go into deadline-risk mode, it's possible that a GPU task won't get scheduled as a result, until the CPU task finishes... all because of this budgeting that you can count out yourself.

To workaround the problem, see if the CPU deadlines aren't too short (a project problem that some projects have), or that your caches aren't too large (which can result in deadlines misses because task completion estimates aren't accurate).

Fun.

It applies at all times.

As an example, let's say you have a GPU app that budgets (1 NVIDIA + 0.501 CPU) for each instance. Let's say you have 2 GPUs, and 8 CPUs, with plenty of tasks available, but the CPU ones all have immediate deadlines.

When the BOINC scheduler runs, it:
- Sees the "deadline miss" CPU tasks
- Schedules them first... 1, 2, 3, ..., 8.
- Allows "up to n+1 CPUs", for any GPU tasks... so, allows budgeting for up-to-9 CPUs.
- Will schedule *1* of your GPU tasks, bringing CPU budget up to 8.501
- Will NOT schedule the 2nd GPU, because that would put the budget to 9.002, which is over the 9.000 limit.

I have a few rigs with multiple GPUs, and also some settings like GPUGrid to run multiple tasks per GPU. So, this exact scenario comes up from time to time.

If CPU tasks go into deadline-risk mode, it's possible that a GPU task won't get scheduled as a result, until the CPU task finishes... all because of this budgeting that you can count out yourself.

To workaround the problem, see if the CPU deadlines aren't too short (a project problem that some projects have), or that your caches aren't too large (which can result in deadlines misses because task completion estimates aren't accurate).

Fun.

^^ Applies if the GPU app is set to use a full CPU thread. That is for combined GPU tasks.