diff --git a/paddle/fluid/framework/device_worker.cc b/paddle/fluid/framework/device_worker.cc
index 579a693503cda..181db5320d7fd 100644
--- a/paddle/fluid/framework/device_worker.cc
+++ b/paddle/fluid/framework/device_worker.cc
@@ -93,8 +93,7 @@ void PrintLodTensorType<float>(phi::DenseTensor* tensor,
                                char separator,
                                bool need_leading_separator,
                                int num_decimals) {
-  std::string buf;
-  buf.resize(MAX_FLOAT_BUFF_SIZE);
+  char buf[MAX_FLOAT_BUFF_SIZE];  // NOLINT
   auto count = tensor->numel();
   if (start < 0 || end > count) {
     VLOG(3) << "access violation";
@@ -109,7 +108,7 @@ void PrintLodTensorType<float>(phi::DenseTensor* tensor,
       out_val += "0";
     } else {
       std::string format = "%." + std::to_string(num_decimals) + "f";
-      sprintf(&buf[0], &format[0], tensor->data<float>()[i]);  // NOLINT
+      sprintf(buf, &format[0], tensor->data<float>()[i]);  // NOLINT
       out_val += buf;
     }
   }