| commit | b7daa2a2f4d09b288026b0c99f86677d513b976d | |
| author | stephen hemminger <shemminger@vyatta.com> | |
| Wed, 4 May 2011 10:04:56 +0000 (4 10:04 +0000) | ||
| committer | Willy Tarreau <w@1wt.eu> | |
| Mon, 19 May 2014 05:54:28 +0000 (19 07:54 +0200) | ||
| tree | 65b57b1439ff0f003d2eb39ee36d2d3143dd1be7 | treesnapshot (tar.gz zip) |
| parent | 18fbf564ddc8a54e5b22961cb50ece22b50cbfba | commitdiff |
tcp_cubic: limit delayed_ack ratio to prevent divide error
TCP Cubic keeps a metric that estimates the amount of delayed
acknowledgements to use in adjusting the window. If an abnormally
large number of packets are acknowledged at once, then the update
could wrap and reach zero. This kind of ACK could only
happen when there was a large window and huge number of
ACK's were lost.
This patch limits the value of delayed ack ratio. The choice of 32
is just a conservative value since normally it should be range of
1 to 4 packets.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit b9f47a3aaeabdce3b42829bbb27765fa340f76ba)
[wt: in 2.6.32, this fix is needed for the next one]
Signed-off-by: Willy Tarreau <w@1wt.eu>
TCP Cubic keeps a metric that estimates the amount of delayed
acknowledgements to use in adjusting the window. If an abnormally
large number of packets are acknowledged at once, then the update
could wrap and reach zero. This kind of ACK could only
happen when there was a large window and huge number of
ACK's were lost.
This patch limits the value of delayed ack ratio. The choice of 32
is just a conservative value since normally it should be range of
1 to 4 packets.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit b9f47a3aaeabdce3b42829bbb27765fa340f76ba)
[wt: in 2.6.32, this fix is needed for the next one]
Signed-off-by: Willy Tarreau <w@1wt.eu>
| net/ipv4/tcp_cubic.c | diffblobblamehistory |