Fix new optimizer lr (#3074)

* default learning rate, temperary fix

* update

go/pserver/client/c/test/test_train.py

@@ -38,7 +38,7 @@ def main():
     parameters = paddle.parameters.create(cost)
 
     # create optimizer of new remote updater to pserver
-    optimizer = paddle.optimizer.Momentum(momentum=0)
+    optimizer = paddle.optimizer.Momentum(momentum=0, learning_rate=1e-3)
 
     print "etcd endoint: ", etcd_endpoint
     trainer = paddle.trainer.SGD(cost=cost,

paddle/trainer/NewRemoteParameterUpdater.cpp

@@ -76,7 +76,11 @@ void NewRemoteParameterUpdater::init(
       sgdConfigV2->set_decay(paramConfig.decay_rate());
       optimizeConfigV2.set_lr_policy(paddle::OptimizerConfig::Const);
       auto constlr = optimizeConfigV2.mutable_const_lr();
-      constlr->set_learning_rate(paramConfig.learning_rate());
+      if (paramConfig.has_learning_rate()) {
+        constlr->set_learning_rate(paramConfig.learning_rate());
+      } else {
+        constlr->set_learning_rate(trainerConfig_.learning_rate());
+      }
       if (trainerConfig_.algorithm() == "sgd") {
         optimizeConfigV2.set_optimizer(paddle::OptimizerConfig::SGD);
         // FIXME: config all algorithms