TL/UCP Special Service Worker

This feature enables a separate UCX UCP worker to use UCC service collectives. In other words, while one service collective may use InfiniBand, another may use TCP.

The feature can be enabled by setting the UCC environment variable as follows:

            

            
-x UCC_TL_UCP_SERVICE_WORKER=1.
        

The service worker is the only UCX worker. A user may pass the UCX configuration for the service worker using the "UCC_TL_UCP_SERVICE_" prefix. For example:

            

            
-x UCC_TL_UCP_SERVICE_NET_DEVICES=mlx5_0:1
        

For further UCC options, run ucc_info -f