Re: [PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-31 Thread Stephen Hemminger
On Mon, 30 Jul 2007 22:21:12 -0700 (PDT) David Miller [EMAIL PROTECTED] wrote: From: Ilpo_Järvinen [EMAIL PROTECTED] Date: Tue, 31 Jul 2007 07:59:10 +0300 (EEST) I think it's probably good to add tp-snd_una != prior_snd_una check there too... It's not going to make a large difference,

Re: [PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-31 Thread David Miller
From: Stephen Hemminger [EMAIL PROTECTED] Date: Tue, 31 Jul 2007 10:51:13 +0100 On Mon, 30 Jul 2007 22:21:12 -0700 (PDT) David Miller [EMAIL PROTECTED] wrote: From: Ilpo_Järvinen [EMAIL PROTECTED] Date: Tue, 31 Jul 2007 07:59:10 +0300 (EEST) I think it's probably good to add

Re: [PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-31 Thread Stephen Hemminger
I noticed no difference in the two flow tests. That is not a bad thing, just that this test doesn't hit that code. The anomaly is that first flow does slow start then gets loss and ends up reducing it's window size all the way to the bottom, finally it recovers. This happens with Cubic, H-TCP

Re: [PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-31 Thread Ilpo Järvinen
On Tue, 31 Jul 2007, Stephen Hemminger wrote: I noticed no difference in the two flow tests. That is not a bad thing, just that this test doesn't hit that code. ...I'm not too sure about your test setup but the bugs I fixed only cover cases that occur if flow is bidirectional (and obviously

[PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-30 Thread Ilpo Järvinen
Actually, the ratehalving seems to work too well, as cwnd is reduced on every second ACK even though the packets in flight remains unchanged. Recoveries in a bidirectional flows suffer quite badly because of this, both NewReno and SACK are affected. After this patch, rate halving is performed

Re: [PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-30 Thread David Miller
From: Ilpo_Järvinen [EMAIL PROTECTED] Date: Mon, 30 Jul 2007 20:18:45 +0300 (EEST) Actually, the ratehalving seems to work too well, as cwnd is reduced on every second ACK even though the packets in flight remains unchanged. Recoveries in a bidirectional flows suffer quite badly because of

Re: [PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-30 Thread Ilpo Järvinen
On Mon, 30 Jul 2007, David Miller wrote: From: Ilpo_Järvinen [EMAIL PROTECTED] Date: Mon, 30 Jul 2007 20:18:45 +0300 (EEST) Actually, the ratehalving seems to work too well, as cwnd is reduced on every second ACK even though the packets in flight remains unchanged. Recoveries in a

Re: [PATCH net-2.6 1/2] [TCP]: Fix ratehalving with bidirectional flows

2007-07-30 Thread David Miller
From: Ilpo_Järvinen [EMAIL PROTECTED] Date: Tue, 31 Jul 2007 07:59:10 +0300 (EEST) I think it's probably good to add tp-snd_una != prior_snd_una check there too... It's not going to make a large difference, mostly just to be conservative when skb collapse stuff got done (and maybe to annoy