diff --git a/paddle/math/RowBuffer.h b/paddle/math/RowBuffer.h
index 9ef5b89680b00981188d78cb312dc75e2c0a79ee..e457d71f1b357aecae48107688499edd7271a5db 100644
--- a/paddle/math/RowBuffer.h
+++ b/paddle/math/RowBuffer.h
@@ -60,7 +60,7 @@ public:
    */
   inline real* get(int row) const {
     if (preallocatedBuf_) {
-      CHECK_LE((row + 1) * width_ * sizeof(real), preallocatedBuf_->getSize());
+      CHECK_LE((row)*width_ * sizeof(real), preallocatedBuf_->getSize());
       return reinterpret_cast<real*>(preallocatedBuf_->getBuf()) + row * width_;
     } else {
       CHECK_LE((row + 1) * width_, rowStore_.size());
diff --git a/paddle/pserver/ParameterClient2.cpp b/paddle/pserver/ParameterClient2.cpp
index 54063a809a4f9e558f8d364f5c437f2b6d98925b..9562c649867a8f82f0262a049398b2f17026a983 100644
--- a/paddle/pserver/ParameterClient2.cpp
+++ b/paddle/pserver/ParameterClient2.cpp
@@ -186,6 +186,7 @@ void ParameterClient2::sendParallel(int tid,
             parameter->getMat(recvParameterType).get());
         CHECK(recvMat);
         size_t width = parameter->getConfig().dims(1);
+        // TODO(wuyi): need add lock here? may also cause resize.
         buf = recvMat->getLocalRow(block.begin_pos() / width);
       }
       /// sparse_id is not useful while receiving data since sparse data
@@ -265,9 +266,9 @@ void ParameterClient2::prepareSendData(
         uint64_t beginDim = 0;
         uint64_t endDim = 0;
 
-        // FIXME(typhoonzero): let it resize first
-        prefetchMat->getLocalRow(nLocalBlocks + 1);
-        sendMat->getLocalRow(nLocalBlocks + 1);
+        // HACK(typhoonzero): let it resize first
+        prefetchMat->getLocalRow(nLocalBlocks);
+        sendMat->getLocalRow(nLocalBlocks);
 
         for (size_t row = 0; row < nLocalBlocks; ++row) {
           int64_t blockId = localIndices[row];  // local row -> sparse row