tensorplay.distributed.algorithms.ddp_comm_hooks.default_hooks.fp16_compress_hook

tensorplay.distributed.algorithms.ddp_comm_hooks.default_hooks.fp16_compress_hook(process_group, bucket)[source]

Compress by casting GradBucket to float16 divided by process group size.

This DDP communication hook implements a simple gradient compression approach that casts GradBucket tensor to half-precision floating-point format (tensorplay.float16) and then divides it by the process group size. It allreduces those float16 gradient tensors. Once compressed gradient tensors are allreduced, the chained callback decompress casts it back to the input data type (such as float32).

Example::

>>> # xdoctest: +SKIP
>>> ddp_model.register_comm_hook(process_group, fp16_compress_hook)