I was noticing a slow down with the GPU app versions on the 15x271 data set. I found the problem - a large fraction of the discriminants were exceeding the hard coded precision. When this happens the GPU kicks it back to the CPU to handle. As a result, the GPU spent more time idling as it waited on the CPU to finish the task. A side effect of this was that the WU would also use almost an entire CPU core.

I increased the hard coded precision and tested on the troublesome data sets as well as the newest 16x271 data set. The issue seems to be fixed, but please report any unexpected behavior.

I guess this falls under unexpected behaviour (of a nice kind). On the 7th UTC I had 6 GPU tasks with a very nice payday. The joys of the credit system the project uses

Why do I keep getting this error?

08/10/19 08:03:51 | NumberFields@home | Finished download of pdtKernel.cl
08/10/19 08:03:51 | NumberFields@home | Finished download of gpuMultiPrec.h
08/10/19 08:03:51 | NumberFields@home | [error] File pdtKernel.cl has wrong size: expected 19580, got 20769
08/10/19 08:03:51 | NumberFields@home | [error] Checksum or signature error for pdtKernel.cl
08/10/19 08:03:51 | NumberFields@home | [error] File gpuMultiPrec.h has wrong size: expected 39042, got 39162
08/10/19 08:03:51 | NumberFields@home | [error] Checksum or signature error for gpuMultiPrec.h

Why do I keep getting this error?

08/10/19 08:03:51 | NumberFields@home | Finished download of pdtKernel.cl
08/10/19 08:03:51 | NumberFields@home | Finished download of gpuMultiPrec.h
08/10/19 08:03:51 | NumberFields@home | [error] File pdtKernel.cl has wrong size: expected 19580, got 20769
08/10/19 08:03:51 | NumberFields@home | [error] Checksum or signature error for pdtKernel.cl
08/10/19 08:03:51 | NumberFields@home | [error] File gpuMultiPrec.h has wrong size: expected 39042, got 39162
08/10/19 08:03:51 | NumberFields@home | [error] Checksum or signature error for gpuMultiPrec.h

So the file size it is expecting is for the old version of the file. I'm not sure why it is doing that, since it is clearly using the latest version of the app (3.04 for opencl nvidia on win64). You might need to reset the project. I checked the results from the 3.04 version of the app and it seems others are not having this problem (at least for the last 500 results).

Going forward I might need to start updating the versions of the opencl files with each app update, to remove any chance of confusion with the client such as you are seeing.