> On Mar 3, 2019, at 5:10 PM, Jonathan Morton <[email protected]> wrote: > >> On 3 Mar, 2019, at 6:07 pm, Pete Heist <[email protected]> wrote: >> >> Does it say anything to you that enabling ECN makes the asymmetry go away? > > Yes - it tells me that it has something directly to do with how dropped > packets are accounted for, not with the congestion response by TCP. ECN > changes the number of dropped packets, and shouldn't change the congestion > response.
That suggests it’s possible to fix. It almost seems like in ingress mode, dropped packets are being counted as bytes transferred, when they weren’t. In the four pcaps I sent, enabling ECN resulted in 0 dropped packets for the N flows down, so it didn’t get to the point where a drop was necessary. Also, the rate of CWR bits set was a bit lower than the rate of drops, and total aggregate throughput was a bit higher. so enabling ECN is a win in this test. _______________________________________________ Cake mailing list [email protected] https://lists.bufferbloat.net/listinfo/cake
