worker 0 doesnt join default index list mapping. use comm.get_num_workers for initializing resources

Author: jlnav

libensemble/resources/worker_resources.py

@@ -102,10 +102,15 @@ def free_rsets(self, worker=None):
 
     @staticmethod
     def get_index_list(num_workers: int, num_rsets: int) -> list[int | None]:
-        """Map WorkerID to index into a nodelist"""
+        """Map WorkerID to index into a nodelist.
+
+        Index 0 is always None since workers are 1-indexed. Worker 0 (gen-on-manager)
+        resource assignment is handled separately. For gen_on_worker mode, worker 0 is
+        never started, so index_list[0] is never accessed.
+        """
         index = 0
-        index_list: list[int | None] = []
-        for i in range(0, num_workers + 1):
+        index_list: list[int | None] = [None]  # index 0: worker 0 not in default rset mapping
+        for i in range(1, num_workers + 1):
             if index >= num_rsets:
                 # Not enough rsets
                 index_list.append(None)

libensemble/worker.py

@@ -223,7 +223,7 @@ def _set_resources(workerID, comm: Comm, libE_specs) -> bool:
         """Sets worker ID in the resources, return True if set"""
         resources = Resources.resources
         if isinstance(resources, Resources):
-            resources.set_worker_resources(comm.get_num_workers() + 1, workerID)
+            resources.set_worker_resources(comm.get_num_workers(), workerID)
             return True
         else:
             logger.debug(f"No resources set on worker {workerID}")