[CP] fix: fix the bug of remote das task performance degradation;

src/sql/engine/dml/ob_table_modify_op.cpp

@@ -1111,6 +1111,9 @@ int ObTableModifyOp::discharge_das_write_buffer()
              "buffer memory", dml_rtctx_.das_ref_.get_das_alloc().used(), K(dml_rtctx_.get_row_buffer_size()));
     ret = submit_all_dml_task();
   } else if (execute_single_row_) {
+    if (REACH_COUNT_INTERVAL(100)) { // print log per 100 times.
+      LOG_TRACE("DML task excute single row", K(execute_single_row_));
+    }
     ret = submit_all_dml_task();
   }
   return ret;