--- a/src/XmlHandler.h	Sun Dec 09 23:27:22 2018 +0100
+++ b/src/XmlHandler.h	Tue Dec 18 13:10:08 2018 +0100
@@ -51,6 +51,8 @@
 	integer_t relationCount = 0;
 
 	const std::string escapeXmlText(const string_t &value) {
+		// TODO: really bad performance → rewrite
+		// 72 % of whole relpipe-out-xml according to valgrind/callgrind
 		std::wstringstream result;
 
 		for (auto & ch : value) {