From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David S. Miller" Subject: Re: bad TSO performance in 2.6.9-rc2-BK Date: Wed, 29 Sep 2004 14:17:31 -0700 Sender: netdev-bounce@oss.sgi.com Message-ID: <20040929141731.2685e561.davem@davemloft.net> References: <20040928223344.GC2975@wotan.suse.de> <20040929090103.GB18671@wotan.suse.de> <20040929125644.40358b42.davem@davemloft.net> <20040929225635.061f2405.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: jheffner@psc.edu, netdev@oss.sgi.com Return-path: To: Andi Kleen In-Reply-To: <20040929225635.061f2405.ak@suse.de> Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On Wed, 29 Sep 2004 22:56:35 +0200 Andi Kleen wrote: > Also the test that John wanted to diable has been in Linux practically > forever (irc dates back to Eric Schenk's work in 2.0) Yes, but it could prove something about either the sender or the receiver, namely that the receive window is not openning up fast enough for some reason, thus delaying the ACKs. > Part of the trace. It looks like the new kernel has really > bad problems with acking. It looks, again, like the receiver's window is not openning up fast enough, which controls ACK response decisions, and that is what jheffner's patch is supposed to verify.