diff options
Diffstat (limited to 'man7/tcp.7')
| -rw-r--r-- | man7/tcp.7 | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/man7/tcp.7 b/man7/tcp.7 index 43251e7b8d..04a7a08ce9 100644 --- a/man7/tcp.7 +++ b/man7/tcp.7 @@ -357,6 +357,39 @@ where packet loss is typically due to random radio interference rather than intermediate router congestion. See RFC 4138 for more details. .TP +.IR tcp_frto_response " (integer; default: 0; since Linux 2.6.22)" +When F-RTO has detected that a TCP retransmission timeout was spurious +(i.e, the timeout would have been avoided had TCP set a +longer retransmission timeout), +TCP has several options concerning what to do next. +Possible values are: +.RS +.IP 0 3 +Rate halving based; a smooth and conservative response, +results in halved congestion window +.RI ( cwnd ) +and slow-start threshold +.RI ( ssthresh ) +after one RTT. +.IP 1 +Very conservative response; not recommended because even +though being valid, it interacts poorly with the rest of +Linux TCP; halves +.I cwnd +and +.I ssthresh +immediately. +.IP 2 +Aggressive response; undoes congestion-control measures +that are now known to be unnecessary +(ignoring the possibility of a lost retransmission that would require +TCP to be more cautious); +.I cwnd +and +.I ssthresh +are restored to the values prior to timeout. +.RE +.TP .IR tcp_keepalive_intvl " (integer; default: 75; since Linux 2.4)" .\" Since 2.3.18 The number of seconds between TCP keep-alive probes. |