refactor inference runners

tensorpack/models/model_desc.py

@@ -80,11 +80,12 @@ class ModelDesc(object):
         for v in input_vars:
             tf.add_to_collection(INPUTS_KEY, v.dumps())
         ret = []
-        for v in input_vars:
-            placehdr_f = tf.placeholder if not v.sparse else tf.sparse_placeholder
-            ret.append(placehdr_f(
-                v.type, shape=v.shape,
-                name=prefix + v.name))
+        with tf.name_scope(None):   # clear any name scope it might get called in
+            for v in input_vars:
+                placehdr_f = tf.placeholder if not v.sparse else tf.sparse_placeholder
+                ret.append(placehdr_f(
+                    v.type, shape=v.shape,
+                    name=prefix + v.name))
         return ret
 
     def get_inputs_desc(self):

tensorpack/train/input_data.py

@@ -85,6 +85,7 @@ class FeedfreeInput(InputData):
         pass
 
 
+# TODO enqueu_many? https://github.com/tensorflow/tensorflow/issues/7817#issuecomment-282053155
 class EnqueueThread(ShareSessionThread):
     def __init__(self, queue, ds, input_placehdrs):
         super(EnqueueThread, self).__init__()