tcp: track min RTT using windowed min-filter

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

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index ebe94f2cab9811e62f0ea1d64c0d6c75838d0367..502d6a572b4ffccd86ce47cdeffe3cd549d89c75 100644 (file)
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -384,6 +384,14 @@ tcp_mem - vector of 3 INTEGERs: min, pressure, max
        Defaults are calculated at boot time from amount of available
        memory.
 
+tcp_min_rtt_wlen - INTEGER
+       The window length of the windowed min filter to track the minimum RTT.
+       A shorter window lets a flow more quickly pick up new (higher)
+       minimum RTT when it is moved to a longer path (e.g., due to traffic
+       engineering). A longer window makes the filter more resistant to RTT
+       inflations such as transient congestion. The unit is seconds.
+       Default: 300
+
 tcp_moderate_rcvbuf - BOOLEAN
        If set, TCP performs receive buffer auto-tuning, attempting to
        automatically size the buffer (no greater than tcp_rmem[2]) to