mindspore.communication.get_group_size

mindspore.communication.get_group_size(group=GlobalComm.WORLD_COMM_GROUP)[source]

Get the rank size of the specified collective communication group.

Note

This method should be used after init().

Parameters

group (str) – The communication group to work on. Normally, the group should be created by create_group, otherwise, using the default group. Default: GlobalComm.WORLD_COMM_GROUP.

Returns

int, the rank size of the group.

Raises

TypeError – If group is not a string.
ValueError – If backend is invalid.
RuntimeError – If HCCL/NCCL/MCCL is not available.

Supported Platforms:: Ascend GPU CPU

Examples

Note

Before running the following examples, you need to configure the communication environment variables.

For Ascend/GPU/CPU devices, it is recommended to use the msrun startup method without any third-party or configuration file dependencies. Please see the msrun start up for more details.

>>> import mindspore as ms
>>> from mindspore.communication import init, get_group_size
>>> init()
>>> group_size = get_group_size()
>>> print("group_size is: ", group_size)
group_size is: 8