Merge pull request #2019 from effigies/fix/mapnode_parallelism

FIX: Copy num_threads to MapNode-generated Nodes

Author: satra

nipype/pipeline/engine/nodes.py

@@ -1112,9 +1112,14 @@ def _make_nodes(self, cwd=None):
             nitems = len(filename_to_list(getattr(self.inputs, self.iterfield[0])))
         for i in range(nitems):
             nodename = '_' + self.name + str(i)
-            node = Node(deepcopy(self._interface), name=nodename)
-            node.overwrite = self.overwrite
-            node.run_without_submitting = self.run_without_submitting
+            node = Node(deepcopy(self._interface),
+                        n_procs=self._interface.num_threads,
+                        mem_gb=self._interface.estimated_memory_gb,
+                        overwrite=self.overwrite,
+                        needed_outputs=self.needed_outputs,
+                        run_without_submitting=self.run_without_submitting,
+                        base_dir=op.join(cwd, 'mapflow'),
+                        name=nodename)
             node.plugin_args = self.plugin_args
             node._interface.inputs.set(
                 **deepcopy(self._interface.inputs.get()))
@@ -1126,7 +1131,6 @@ def _make_nodes(self, cwd=None):
                 logger.debug('setting input %d %s %s', i, field, fieldvals[i])
                 setattr(node.inputs, field, fieldvals[i])
             node.config = self.config
-            node.base_dir = op.join(cwd, 'mapflow')
             yield i, node
 
     def _node_runner(self, nodes, updatehash=False):

nipype/pipeline/engine/tests/test_engine.py

@@ -486,6 +486,28 @@ def func1(in1):
     assert "can only concatenate list" in str(excinfo.value)
 
 
+def test_mapnode_expansion(tmpdir):
+    os.chdir(str(tmpdir))
+    from nipype import MapNode, Function
+
+    def func1(in1):
+        return in1 + 1
+
+    mapnode = MapNode(Function(function=func1),
+                      iterfield='in1',
+                      name='mapnode')
+    mapnode.inputs.in1 = [1, 2]
+    mapnode.interface.num_threads = 2
+    mapnode.interface.estimated_memory_gb = 2
+
+    for idx, node in mapnode._make_nodes():
+        for attr in ('overwrite', 'run_without_submitting', 'plugin_args'):
+            assert getattr(node, attr) == getattr(mapnode, attr)
+        for attr in ('num_threads', 'estimated_memory_gb'):
+            assert (getattr(node._interface, attr) ==
+                    getattr(mapnode._interface, attr))
+
+
 def test_node_hash(tmpdir):
     wd = str(tmpdir)
     os.chdir(wd)