From: "Ilpo_Järvinen" <[EMAIL PROTECTED]> Date: Fri, 2 Mar 2007 14:34:36 +0200 (EET)
> Undoing ssthresh is disabled in fastretrans_alert whenever > FLAG_ECE is set by clearing prior_ssthresh. The clearing does > not protect FRTO because FRTO operates before fastretrans_alert. > Moving the clearing of prior_ssthresh earlier seems to be a > suboptimal solution to the FRTO case because then FLAG_ECE will > cause a second ssthresh reduction in try_to_open (the first > occurred when FRTO was entered). So instead, FRTO falls back > immediately to the rate halving response, which switches TCP to > CA_CWR state preventing the latter reduction of ssthresh. > > If the first ECE arrived before the ACK after which FRTO is able > to decide RTO as spurious, prior_ssthresh is already cleared. > Thus no undoing for ssthresh occurs. Besides, FLAG_ECE should be > set also in the following ACKs resulting in rate halving response > that sees TCP is already in CA_CWR, which again prevents an extra > ssthresh reduction on that round-trip. > > If the first ECE arrived before RTO, ssthresh has already been > adapted and prior_ssthresh remains cleared on entry because TCP > is in CA_CWR (the same applies also to a case where FRTO is > entered more than once and ECE comes in the middle). > > High_seq must not be touched after tcp_enter_cwr because CWR > round-trip calculation depends on it. > > I believe that after this patch, FRTO should be ECN-safe and > even able to take advantage of synergy benefits. > > Signed-off-by: Ilpo Järvinen <[EMAIL PROTECTED]> Applied, but I had to apply this by hand, you did not generate this diff against tcp-2.6 And I'm very angry about this specific case because I told you EXPLICITLY that I reformated the switch() statement when I applied the earlier FRTO patches. Not only are people expected to patch against tcp-2.6, BUT I TOLD YOU specifically that I modified your patch in this specific area. What else do I need to do in order for people to generate clean patches? :-( Tell me, I'll do it!!! - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
