Adding the exclusive topology by hostname for the head job

Changing the name of the worker container to pathways-worker

Author: lukebaumann

axlearn/cloud/gcp/pathways_utils.py

@@ -429,6 +429,11 @@ def _build_pathways_head_job(self):
         annotations = _LoadBalancer(
             jobset_name=cfg.name, replicated_job_name=_PATHWAYS_HEAD_REPLICATED_JOB_NAME
         ).metadata
+        annotations.update(
+            {
+                "alpha.jobset.sigs.k8s.io/exclusive-topology": "kubernetes.io/hostname",
+            }
+        )
         spec = dict(
             parallelism=1,
             completions=1,
@@ -451,6 +456,8 @@ def _build_pathways_worker_container(
         container = self._inner._build_container()
 
         worker_container = copy.deepcopy(container)
+        worker_container["name"] = "pathways-worker"
+
         env_list = worker_container.get("env", [])
 
         pathways_head_address = self._get_pathways_head_address(