get_rank_id

Description

Obtains the rank ID of a device in a group.

Prototype

def get_rank_id(group="hccl_world_group")

Parameters

Parameter	Input/Output	Description
group	Input	A string containing a maximum of 128 bytes, including the end character. Group name, which is user-defined. If no argument is passed, the default value hccl_world_group is used.

Parameter

Input/Output

Description

group

Input

A string containing a maximum of 128 bytes, including the end character.

Group name, which is user-defined. If no argument is passed, the default value hccl_world_group is used.

Returns

An int for the rank ID of the group to which the device belongs

Constraints

This API must be called after the initialization of collective communication is complete.
The caller rank must be within the range defined by the group argument passed to this API call. Otherwise, the API call fails.
After the create_group call, call this API to obtain the rank ID of a process in a group.
If hccl_world_group is passed, the rank ID of the process in hccl_world_group is returned.

Applicability

Atlas Training Series Product

Example

The following is only a code snippet and cannot be executed. For details about how to call the HCCL Python APIs to perform collective communication, see Sample Code.

from npu_bridge.npu_init import *
create_group("myGroup", 4, [0, 1, 2, 3])
rankId = get_rank_id("myGroup")

Parent topic: hccl.manage.api