Re: [PATCH net] tcp: disallow cwnd undo when switching congestion control

2017-06-02 Thread David Miller
From: Yuchung Cheng Date: Wed, 31 May 2017 11:21:27 -0700 > When the sender switches its congestion control during loss > recovery, if the recovery is spurious then it may incorrectly > revert cwnd and ssthresh to the older values set by a previous > congestion control.

Re: [PATCH net] tcp: disallow cwnd undo when switching congestion control

2017-05-31 Thread Yuchung Cheng
On Wed, May 31, 2017 at 11:47 AM, Stephen Hemminger wrote: > > On Wed, 31 May 2017 11:21:27 -0700 > Yuchung Cheng wrote: > > > When the sender switches its congestion control during loss > > recovery, if the recovery is spurious then it may

Re: [PATCH net] tcp: disallow cwnd undo when switching congestion control

2017-05-31 Thread Stephen Hemminger
On Wed, 31 May 2017 11:21:27 -0700 Yuchung Cheng wrote: > When the sender switches its congestion control during loss > recovery, if the recovery is spurious then it may incorrectly > revert cwnd and ssthresh to the older values set by a previous > congestion control. Consider

[PATCH net] tcp: disallow cwnd undo when switching congestion control

2017-05-31 Thread Yuchung Cheng
When the sender switches its congestion control during loss recovery, if the recovery is spurious then it may incorrectly revert cwnd and ssthresh to the older values set by a previous congestion control. Consider a congestion control (like BBR) that does not use ssthresh and keeps it infinite: