diff options
Diffstat (limited to 'Documentation/networking')
-rw-r--r-- | Documentation/networking/ip-sysctl.txt | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 32c2e9da5f3a..6ae2feff3087 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt | |||
@@ -180,13 +180,20 @@ tcp_fin_timeout - INTEGER | |||
180 | to live longer. Cf. tcp_max_orphans. | 180 | to live longer. Cf. tcp_max_orphans. |
181 | 181 | ||
182 | tcp_frto - INTEGER | 182 | tcp_frto - INTEGER |
183 | Enables F-RTO, an enhanced recovery algorithm for TCP retransmission | 183 | Enables Forward RTO-Recovery (F-RTO) defined in RFC4138. |
184 | F-RTO is an enhanced recovery algorithm for TCP retransmission | ||
184 | timeouts. It is particularly beneficial in wireless environments | 185 | timeouts. It is particularly beneficial in wireless environments |
185 | where packet loss is typically due to random radio interference | 186 | where packet loss is typically due to random radio interference |
186 | rather than intermediate router congestion. If set to 1, basic | 187 | rather than intermediate router congestion. FRTO is sender-side |
187 | version is enabled. 2 enables SACK enhanced F-RTO, which is | 188 | only modification. Therefore it does not require any support from |
188 | EXPERIMENTAL. The basic version can be used also when SACK is | 189 | the peer, but in a typical case, however, where wireless link is |
189 | enabled for a flow through tcp_sack sysctl. | 190 | the local access link and most of the data flows downlink, the |
191 | faraway servers should have FRTO enabled to take advantage of it. | ||
192 | If set to 1, basic version is enabled. 2 enables SACK enhanced | ||
193 | F-RTO if flow uses SACK. The basic version can be used also when | ||
194 | SACK is in use though scenario(s) with it exists where FRTO | ||
195 | interacts badly with the packet counting of the SACK enabled TCP | ||
196 | flow. | ||
190 | 197 | ||
191 | tcp_frto_response - INTEGER | 198 | tcp_frto_response - INTEGER |
192 | When F-RTO has detected that a TCP retransmission timeout was | 199 | When F-RTO has detected that a TCP retransmission timeout was |