tcp: Tail loss probe (TLP)

[karo-tx-linux.git] / Documentation / networking / ip-sysctl.txt

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index dc2dc87d2557b4fdf7537b9e8f4185965c3dd1ce..1cae6c383e1b781cc6a6e2b424d973ccecb811e6 100644 (file)
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -190,7 +190,9 @@ tcp_early_retrans - INTEGER
        Enable Early Retransmit (ER), per RFC 5827. ER lowers the threshold
        for triggering fast retransmit when the amount of outstanding data is
        small and when no previously unsent data can be transmitted (such
-       that limited transmit could be used).
+       that limited transmit could be used). Also controls the use of
+       Tail loss probe (TLP) that converts RTOs occuring due to tail
+       losses into fast recovery (draft-dukkipati-tcpm-tcp-loss-probe-01).
        Possible values:
                0 disables ER
                1 enables ER
@@ -198,7 +200,9 @@ tcp_early_retrans - INTEGER
                  by a fourth of RTT. This mitigates connection falsely
                  recovers when network has a small degree of reordering
                  (less than 3 packets).
-       Default: 2
+               3 enables delayed ER and TLP.
+               4 enables TLP only.
+       Default: 3
 
 tcp_ecn - INTEGER
        Control use of Explicit Congestion Notification (ECN) by TCP.