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Altera_Forum
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12 years ago

opencl program and kernel object limits + retaining buffers

Hi, I'm currently experiencing problems when creating a number of program objects under OpenCL, I'm getting "host out of memory" errors on a Stratix D5 FPGA. I believe that I may be hitting a ...
Altera_Forum's avatar
Altera_Forum
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12 years ago

Regarding memory being wiped: these buffers are actually copied to the host side to preserve them so no need to worry about them being deleted/freed. However, this may incur some slight performance penalty when context switching between OpenCL programs.

The limit of 32 kernels is per OpenCL program (aocx file). The limit of 20 OpenCL programs per host program. That is why you are seeing this error message.

My recommendation is to try to squeeze more kernels per program, if at all possible. Future releases may increase the number of active OpenCL programs but this is not determined yet. We will take your comments into consideration.