add splitter

python/paddle/v2/fluid/distribute_transpiler.py

@@ -80,7 +80,6 @@ class DistributeTranspiler:
 
         # step3
         send_inputs = []
-        send_outputs = []
         for _, splited in var2splited.iteritems():
             send_inputs.extend(splited)
         send_outputs = self._create_vars_from_blocklist(program, param_blocks)

python/paddle/v2/fluid/distributed_spliter.py

@@ -0,0 +1,38 @@
+def hash_name(varblocks, pserver_endpoints):
+    """
+    :param varblocks: a list of VarBlock string indicating 
+                      sub blocks of variables
+    :return: a map of pserver endpoint -> varblock_str
+    """
+
+    def _hash_block(block_str, total):
+        return hash(block_str) % total
+
+    ep2block = dict()
+    for varblock_str in varblocks:
+        if param.trainable is True and grad is not None:
+            server_id = _hash_block(varblock_str, len(pserver_endpoints))
+            server_for_param = pserver_endpoints[server_id]
+            if not ep2block.has_key(server_for_param):
+                ep2block[server_for_param] = []
+            ep2block[server_for_param].append(varblock_str)
+
+    return ep2block
+
+
+def round_robin(varblocks, pserver_endpoints):
+    assert (len(varblocks) > len(pserver_endpoints))
+
+    ep2block = dict()
+    pserver_idx = 0
+    for varblock_str in varblocks:
+        if param.trainable is True:
+            server_for_param = pserver_endpoints[pserver_idx]
+            if not ep2block.has_key(server_for_param):
+                ep2block[server_for_param] = []
+            ep2block[server_for_param].append(varblock_str)
+
+            pserver_idx += 1
+            if pserver_idx >= len(pserver_endpoints):
+                pserver_idx = 0
+    return ep2block