Support for torch DDP + ipex + bf16

[Peach-He]

According the ipex doc, torch DDP with bf16 with ipex is not supported, so we cannot use ipex optimization in this scenario, right?
Do we have the plan to add support for torch DDP + ipex + bf16?

[jgong5]

cc @liangan1

[liangan1]

According the ipex doc, torch DDP with bf16 with ipex is not supported, so we cannot use ipex optimization in this scenario, right?
Do we have the plan to add support for torch DDP + ipex + bf16?

BF16 is not supported by the default communication backend(eg, gloo,mpi) in the torch. To use BF16 distributed training with IPEX, You can use DDP+IPEX+BF16+Torch-ccl(https://github.com/intel/torch-ccl/tree/ccl_torch1.10).