diff --git a/ChangeLog b/ChangeLog
index f00f1a55d..c05a49957 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -24,6 +24,7 @@
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
+	* uTP performance improvement. only fast retransmit one packet at a time
 	* improve error message for 'file too short'
 	* fix piece-picker stat bug when only selecting some files for download
 	* fix bug in async_add_torrent when settings file_priorities
diff --git a/src/utp_stream.cpp b/src/utp_stream.cpp
index 6c72b6f19..7ff1a7333 100644
--- a/src/utp_stream.cpp
+++ b/src/utp_stream.cpp
@@ -110,7 +110,12 @@ enum
 
 	// the max number of packets to fast-resend per
 	// selective ack message
-	sack_resend_limit = 3,
+	// only re-sending a single packet per sack
+	// appears to improve performance by making it
+	// less likely to loose the re-sent packet. Because
+	// when that happens, we must time-out in order
+	// to continue, which takes a long time.
+	sack_resend_limit = 1,
 };
 
 // compare if lhs is less than rhs, taking wrapping