diff --git a/cpp/connector/kafka/sink/KafkaWriter.cpp b/cpp/connector/kafka/sink/KafkaWriter.cpp
index 6b7738d642d3438ab8609f6406599245dabc611a..3fe7362005e0b8d6df0981dfb4d6b23a4af016f9 100644
--- a/cpp/connector/kafka/sink/KafkaWriter.cpp
+++ b/cpp/connector/kafka/sink/KafkaWriter.cpp
@@ -78,6 +78,7 @@ void KafkaWriter::write(String *element)
     }
     auto record = recordSerializer->Serialize(element);
     ProduceRecord(record);
+    delete element;
 }
 
 void KafkaWriter::write(Row *element)
diff --git a/cpp/connector/kafka/sink/KafkaWriter.h b/cpp/connector/kafka/sink/KafkaWriter.h
index 17696bac4aab2c250125c742c9530eee85aaa75f..1e78fd14adf012e56bd68c19c9eeeae0fd4c078c 100644
--- a/cpp/connector/kafka/sink/KafkaWriter.h
+++ b/cpp/connector/kafka/sink/KafkaWriter.h
@@ -139,7 +139,7 @@ private:
         while (timer_worker_thread_flag.load()) {
             clock_gettime(CLOCK_MONOTONIC, &end);
             // 计算时间差
-            long ns = (end.tv_sec - start.tv_sec) * 1000000000L + (end.tv_nsec - start.tv_nsec);
+            uint64_t ns = (end.tv_sec - start.tv_sec) * 1000000000L + (end.tv_nsec - start.tv_nsec);
             if (ns >= 5000000000L) {
                 handleRecord();
                 start = end;