add program cache for executor

Author: jacquesqiao

python/paddle/fluid/executor.py

@@ -177,6 +177,7 @@ def __init__(self, places):
         # TODO(dzhwinter) : only use the first place
         self.executor = core.Executor(act_places[0])
         self.places = places
+        self.program_caches = dict()
 
     def aslodtensor(self, data):
         def accumulate(data):
@@ -240,56 +241,63 @@ def run(self,
         if scope is None:
             scope = global_scope()
 
-        program = program.clone()
-        global_block = program.global_block()
+        program_cache_key = str(feed.keys() + fetch_list)
+        program_cache = self.program_caches.get(program_cache_key, None)
 
-        if feed_var_name in global_block.vars:
-            feed_var = global_block.var(feed_var_name)
-        else:
-            feed_var = global_block.create_var(
-                name=feed_var_name,
-                type=core.VarDesc.VarType.FEED_MINIBATCH,
-                persistable=True)
+        if program_cache is None:
+            program_cache = program.clone()
+            self.program_caches[program_cache_key] = program_cache
 
-        if fetch_var_name in global_block.vars:
-            fetch_var = global_block.var(fetch_var_name)
-        else:
-            fetch_var = global_block.create_var(
-                name=fetch_var_name,
-                type=core.VarDesc.VarType.FETCH_LIST,
-                persistable=True)
-
-        if not has_feed_operators(global_block, feed, feed_var_name):
-            for i, name in enumerate(feed):
-                out = global_block.var(name)
-                global_block.prepend_op(
-                    type='feed',
-                    inputs={'X': [feed_var]},
-                    outputs={'Out': [out]},
-                    attrs={'col': i})
-
-        for op in global_block.ops:
-            if op.desc.type() == 'feed':
-                feed_target_name = op.desc.output('Out')[0]
-                cur_feed = feed[feed_target_name]
-                if not isinstance(cur_feed, core.LoDTensor):
-                    cur_feed = self.aslodtensor(cur_feed)
-                idx = op.desc.attr('col')
-                core.set_feed_variable(scope, cur_feed, feed_var_name, idx)
+            global_block = program_cache.global_block()
+
+            if feed_var_name in global_block.vars:
+                feed_var = global_block.var(feed_var_name)
+            else:
+                feed_var = global_block.create_var(
+                    name=feed_var_name,
+                    type=core.VarDesc.VarType.FEED_MINIBATCH,
+                    persistable=True)
+
+            if fetch_var_name in global_block.vars:
+                fetch_var = global_block.var(fetch_var_name)
             else:
-                break
-
-        if not has_fetch_operators(global_block, fetch_list, fetch_var_name):
-            for i, var in enumerate(fetch_list):
-                assert isinstance(var, Variable) or isinstance(var, str), (
-                    "Wrong type for fetch_list[%s]: %s" % (i, type(var)))
-                global_block.append_op(
-                    type='fetch',
-                    inputs={'X': [var]},
-                    outputs={'Out': [fetch_var]},
-                    attrs={'col': i})
-
-        self.executor.run(program.desc, scope, 0, True, True)
+                fetch_var = global_block.create_var(
+                    name=fetch_var_name,
+                    type=core.VarDesc.VarType.FETCH_LIST,
+                    persistable=True)
+
+            if not has_feed_operators(global_block, feed, feed_var_name):
+                for i, name in enumerate(feed):
+                    out = global_block.var(name)
+                    global_block.prepend_op(
+                        type='feed',
+                        inputs={'X': [feed_var]},
+                        outputs={'Out': [out]},
+                        attrs={'col': i})
+
+            for op in global_block.ops:
+                if op.desc.type() == 'feed':
+                    feed_target_name = op.desc.output('Out')[0]
+                    cur_feed = feed[feed_target_name]
+                    if not isinstance(cur_feed, core.LoDTensor):
+                        cur_feed = self.aslodtensor(cur_feed)
+                    idx = op.desc.attr('col')
+                    core.set_feed_variable(scope, cur_feed, feed_var_name, idx)
+                else:
+                    break
+
+            if not has_fetch_operators(global_block, fetch_list,
+                                       fetch_var_name):
+                for i, var in enumerate(fetch_list):
+                    assert isinstance(var, Variable) or isinstance(var, str), (
+                        "Wrong type for fetch_list[%s]: %s" % (i, type(var)))
+                    global_block.append_op(
+                        type='fetch',
+                        inputs={'X': [var]},
+                        outputs={'Out': [fetch_var]},
+                        attrs={'col': i})
+
+        self.executor.run(program_cache.desc, scope, 0, True, True)
         outs = [
             core.get_fetch_variable(scope, fetch_var_name, i)
             for i in xrange(len(fetch_list))