Exposed processpool num workers setting

alchemiscale_fah/compute/service.py

@@ -399,7 +399,7 @@ def cycle_init(self):
         self._start_time = time.time()
 
         # create process pool
-        self._pool = ProcessPoolExecutor()
+        self._pool = ProcessPoolExecutor(self.settings.max_processpool_workers)
 
         # open index
         self.index = FahComputeServiceIndex(self.index_dir, self.obj_store)

alchemiscale_fah/compute/settings.py

@@ -9,6 +9,12 @@
 class FahAsynchronousComputeServiceSettings(ComputeServiceSettings):
     """Settings schema for a FahSynchronousComputeService."""
 
+    # Maximum number of workers to allocate to the service's process pool
+    max_processpool_workers: Optional[int] = Field(
+        None,
+        description="Maximum number of workers to allocate to the service's process pool; `None` will default to number of processors on host.",
+    )
+
     fah_as_url: str = Field(
         ...,
         description="URL of the FAH assignment server to use.",

devtools/configs/fah-asynchronous-compute-settings.yaml

@@ -78,6 +78,10 @@ init:
 
   ## FAH-specific settings
 
+  # Maximum number of workers to allocate to the service's process pool;
+  # `null` will default to number of processors on host.
+  max_processpool_workers: null
+
   # URL of the FAH assignment server to use.
   fah_as_url: "https://assign1.foldingathome.org"