def set_jit_fusion_options():
    """Set PyTorch JIT layer fusion options."""
    # flags required to enable jit fusion kernels
    TORCH_MAJOR = int(torch.__version__.split(".")[0])
    TORCH_MINOR = int(torch.__version__.split(".")[1])
    if (TORCH_MAJOR > 1) or (TORCH_MAJOR == 1 and TORCH_MINOR >= 10):
        # nvfuser
        torch._C._jit_set_profiling_executor(True)
        torch._C._jit_set_profiling_mode(True)
        torch._C._jit_override_can_fuse_on_cpu(False)
        torch._C._jit_override_can_fuse_on_gpu(False)
        torch._C._jit_set_texpr_fuser_enabled(False)
        torch._C._jit_set_nvfuser_enabled(True)
        torch._C._debug_set_autodiff_subgraph_inlining(False)
    else:
        # legacy pytorch fuser
        torch._C._jit_set_profiling_mode(False)
        torch._C._jit_set_profiling_executor(False)
        torch._C._jit_override_can_fuse_on_cpu(True)
        torch._C._jit_override_can_fuse_on_gpu(True)

    _warmup_jit_function()
Set PyTorch JIT layer fusion options.
training/DeepSpeed-Domino/megatron/initialize.py