[TCP] FRTO: Sysctl documentation for SACK enhanced version
The description is overly verbose to avoid ambiguity between
"SACK enabled" and "SACK enhanced FRTO"
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 702d1d8..719b429 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -183,7 +183,10 @@
Enables F-RTO, an enhanced recovery algorithm for TCP retransmission
timeouts. It is particularly beneficial in wireless environments
where packet loss is typically due to random radio interference
- rather than intermediate router congestion.
+ rather than intermediate router congestion. If set to 1, basic
+ version is enabled. 2 enables SACK enhanced FRTO, which is
+ EXPERIMENTAL. The basic version can be used also when SACK is
+ enabled for a flow through tcp_sack sysctl.
tcp_keepalive_time - INTEGER
How often TCP sends out keepalive messages when keepalive is enabled.