feat(dask): set maximum limit for number of workers (#712)

reanahub · Nov 5, 2024 · cdba3b1 · cdba3b1
1 parent 15d0b97
commit cdba3b1
Show file tree

Hide file tree

Showing 2 changed files with 12 additions and 0 deletions.
diff --git a/reana_server/config.py b/reana_server/config.py
@@ -71,6 +71,11 @@
 )
 """Number of workers in Dask cluster by default """
 
+REANA_DASK_CLUSTER_MAX_NUMBER_OF_WORKERS = int(
+    os.getenv("REANA_DASK_CLUSTER_MAX_NUMBER_OF_WORKERS", 20)
+)
+"""Maximum number of workers in Dask cluster."""
+
 REANA_DASK_CLUSTER_DEFAULT_SINGLE_WORKER_MEMORY = os.getenv(
     "REANA_DASK_CLUSTER_DEFAULT_SINGLE_WORKER_MEMORY", "2Gi"
 )

diff --git a/reana_server/validation.py b/reana_server/validation.py
@@ -26,6 +26,7 @@
     DASK_ENABLED,
     REANA_DASK_CLUSTER_MAX_MEMORY_LIMIT,
     REANA_DASK_CLUSTER_DEFAULT_NUMBER_OF_WORKERS,
+    REANA_DASK_CLUSTER_MAX_NUMBER_OF_WORKERS,
     REANA_DASK_CLUSTER_DEFAULT_SINGLE_WORKER_MEMORY,
     REANA_DASK_CLUSTER_MAX_SINGLE_WORKER_MEMORY,
 )
@@ -188,6 +189,12 @@ def validate_dask_memory_and_cores_limits(reana_yaml: Dict) -> None:
                 "number_of_workers", REANA_DASK_CLUSTER_DEFAULT_NUMBER_OF_WORKERS
             )
         )
+
+        if number_of_workers > REANA_DASK_CLUSTER_MAX_NUMBER_OF_WORKERS:
+            raise REANAValidationError(
+                f'The "number_of_workers" provided in the dask resources exceeds the limit ({REANA_DASK_CLUSTER_MAX_NUMBER_OF_WORKERS}).'
+            )
+
         requested_dask_cluster_memory = (
             kubernetes_memory_to_bytes(single_worker_memory) * number_of_workers
         )