gradInput is nil when training with multiple GPUs with DataParallelTable
bearpaw opened this issue · comments
Wei Yang commented
Hi all,
When training on a single GPU, the gradInput
is returned correctly after calling :backward
.
However, when using with DataParallelTable
, the gradInput
is nil
after backward. Is this a bug of nngraph when using with DataParallelTable
?
Wei Yang commented
I found it is related to DataParallelTable
. The gradInput
in DataParallelTable
is actually saved as gradInputGpu
from the source code