diff --git a/celldetection_scripts/cpn_inference.py b/celldetection_scripts/cpn_inference.py
index 2a87d62..c7b9aea 100644
--- a/celldetection_scripts/cpn_inference.py
+++ b/celldetection_scripts/cpn_inference.py
@@ -377,6 +377,8 @@ def cpn_inference(
         model_kwargs: Union[Dict[str, Any], List[Dict[str, Any]], str, List[str]] = None,
         group_level: str = 'job',
         continue_on_exception: bool = False,
+        return_results: bool = False,
+        num_nodes: Union[str, int] = 'auto',
 ):
     """
     Process contour proposals for instance segmentation using specified parameters.
@@ -444,6 +446,9 @@ def cpn_inference(
             ensured for example via `CUDA_VISIBLE_DEVICES` for GPUs.
         continue_on_exception (bool): If ``True``, try to continue processing when certain Exceptions are raised.
             Only works for selected stages (e.g. loading of an input file).
+        return_results (bool): Whether to return results. Should be False when used for long sequences of large inputs,
+            as collection of large results can lead to OOM exception.
+        num_nodes (int): Number of nodes. Default is 'auto'.
     """
 
     args = dict(locals())
@@ -572,7 +577,10 @@ def resolve_inputs_(collection, x, tag='inputs'):
         ]))
 
     # Load model
+    if num_nodes == 'auto':
+        num_nodes = cd.get_num_nodes()
     trainer = pl.Trainer(
+        num_nodes=num_nodes,
         accelerator=accelerator,
         strategy=strategy,
         devices=devices,
@@ -689,7 +697,8 @@ def load_inputs(x, dataset_name, method, tag, idx, ext_checks=('.h5',)):
 
         is_dist = is_available() and is_initialized()
         output = cd.asnumpy(y)
-        output_list.append(output)
+        if return_results:
+            output_list.append(output)
         out_files = dict()
         if (is_dist and get_rank() == 0) or not is_dist:
             props = properties
@@ -756,7 +765,8 @@ def load_inputs(x, dataset_name, method, tag, idx, ext_checks=('.h5',)):
     if cd.mpi.has_mpi():
         comm.barrier()
 
-    return output_list
+    if return_results:
+        return output_list
 
 
 def main():
@@ -843,7 +853,7 @@ def d(name):
                         help='Separator string for region properties that are written to multiple columns. '
                              'Default is "-" as in bbox-0, bbox-1, bbox-2, bbox-4.')
 
-    parser.add_argument('--group_level', type=str,
+    parser.add_argument('--group_level', type=str, default='job',
                         help='Processing group level. One of `("job", "node", "rank")`, indicating the scope of '
                              'processing groups that jointly process the same inputs. `"rank"` indicates for example '
                              'that each input is processed by just one rank.')
@@ -906,7 +916,8 @@ def d(name):
         model_parameters=args.model_parameters,
         skip_existing=args.skip_existing,
         model_kwargs=args.model_kwargs,
-        group_level=args.group_level
+        group_level=args.group_level,
+        return_results=False,
     )
 
     if not (is_available() and is_initialized()) or get_rank() == 0:  # because why not