On Tue, May 29, 2018 at 12:03:46PM -0400, Neal Cardwell wrote: > On Tue, May 29, 2018 at 11:45 AM Marcelo Ricardo Leitner < > marcelo.leitner@xxxxxxxxx> wrote: > > - patch2 - fix rtx attack vector > > - Add the floor value to rto_min to HZ/20 (which fits the values > > that Michael shared on the other email) > > I would encourage allowing minimum RTO values down to 5ms, if the ACK > policy in the receiver makes this feasible. Our experience is that in > datacenter environments it can be advantageous to allow timer-based loss > recoveries using timeout values as low as 5ms, e.g.: Thanks Neal. On Xin's tests, the hearbeat timer becomes an issue at ~25ms already. Xin, can you share more details on the hw, which CPU was used? Anyway, what about we add a floor to rto_max too, so that RTO can actually grow into something bigger that don't hog the CPU? Like: rto_min floor = 5ms rto_max floor = 50ms Marcelo -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html