diff --git a/onnxsim/onnx_simplifier.py b/onnxsim/onnx_simplifier.py
index 20056f3..ad72904 100644
--- a/onnxsim/onnx_simplifier.py
+++ b/onnxsim/onnx_simplifier.py
@@ -228,6 +228,9 @@ def check_node(graph):
                 # Skip QuantizeLinear and DequantizeLinear to preserve quantization info
                 pass
             elif all([x in const_tensors for x in node.input]) and not is_non_deterministic_node(node):
+                # Skip these nodes to avoid bloating the model size
+                if node.op_type in ['ConstantOfShape', 'Tile']:
+                    continue
                 const_nodes.append(node)
                 const_tensors.extend(node.output)
 
@@ -305,13 +308,6 @@ def forward_for_node_outputs(model: onnx.ModelProto,
     return res
 
 
-def insert_elem(repeated_container, index: int, element):
-    repeated_container.extend([repeated_container[-1]])
-    for i in reversed(range(index + 1, len(repeated_container) - 1)):
-        repeated_container[i].CopyFrom(repeated_container[i - 1])
-    repeated_container[index].CopyFrom(element)
-
-
 def eliminate_const_nodes(model: onnx.ModelProto, const_nodes: Sequence[onnx.NodeProto],
                           res: Tensors) -> onnx.ModelProto:
     """
@@ -321,6 +317,7 @@ def eliminate_const_nodes(model: onnx.ModelProto, const_nodes: Sequence[onnx.Nod
     :return: the simplified onnx model. Redundant ops are all removed.
     """
     def recursive_eliminate_const_nodes_in_graph(graph, const_nodes, res):
+        new_nodes = []
         for i, node in enumerate(graph.node):
             if node in const_nodes:
                 for output in node.output:
@@ -336,12 +333,17 @@ def recursive_eliminate_const_nodes_in_graph(graph, const_nodes, res):
                     del new_node.output[:]
                     new_node.output.extend([output])
                     new_node.attribute.extend([new_attr])
-                    insert_elem(graph.node, i + 1, new_node)
-                del graph.node[i]
-            if has_subgraph_in_node(node):
-                for attr in node.attribute:
-                    recursive_eliminate_const_nodes_in_graph(
-                        attr.g, const_nodes, res)
+                    new_nodes.append(new_node)
+            else:
+                new_nodes.append(node)
+                if has_subgraph_in_node(node):
+                    for attr in node.attribute:
+                        if attr.g is None:
+                            continue
+                        recursive_eliminate_const_nodes_in_graph(
+                            attr.g, const_nodes, res)
+        del graph.node[:]
+        graph.node.extend(new_nodes)
     recursive_eliminate_const_nodes_in_graph(model.graph, const_nodes, res)
 
     return model
@@ -471,8 +473,7 @@ def fixed_point(x: T, func_a: Callable[[T], T], func_b: Callable[[T], T]) -> T:
     """
     x = func_a(x)
     x = func_b(x)
-    count = 0
-    for _ in range(64):
+    for _ in range(int(os.getenv('ONNXSIM_FIXED_POINT_MAX_ITER', '5'))):
         y = func_a(x)
         if y == x:
             # Since func_b(func_b(x)) == func_b(x),
@@ -484,7 +485,6 @@ def fixed_point(x: T, func_a: Callable[[T], T], func_b: Callable[[T], T]) -> T:
         if y == x:
             return x
         x = y
-    print("Warning: The simplifying takes too long. Stopping..")
     return x