"writeback=True" is not currently supported and will raise an
        error. This is because model parameter shapes would be
        different across ranks within the context, and writing to them
        can lead to inconsistency across ranks when the context is
        exited.
  Warning:

    Note that "offload_to_cpu" and "rank0_only=False" will result
    in full parameters being redundantly copied to CPU memory for
    GPUs that reside on the same machine, which may incur the risk
    of CPU OOM. It is recommended to use "offload_to_cpu" with
    "rank0_only=True".

  Parameters:
     * **recurse** (*bool**, **Optional*) -- recursively summon
       all params for nested FSDP instances (default: True).

     * **writeback** (*bool**, **Optional*) -- if "False",
       modifications to params are discarded after the context
       manager exits; disabling this can be slightly more
       efficient (default: True)
