From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nivedita Singhvi Subject: Re: bad TSO performance in 2.6.9-rc2-BK Date: Wed, 29 Sep 2004 14:16:55 -0700 Sender: netdev-bounce@oss.sgi.com Message-ID: <415B2647.8080803@us.ibm.com> References: <20040928223344.GC2975@wotan.suse.de> <20040929140016.7ffa4e8b.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: John Heffner , ak@suse.de, netdev@oss.sgi.com Return-path: To: "David S. Miller" In-Reply-To: <20040929140016.7ffa4e8b.davem@davemloft.net> Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org David S. Miller wrote: > I think you hit the jackpot John... or at least you're > on the right trail. > > It seems I'll have to do some send buffer liberation when > we partially ACK TSO frames. Since that isn't happening > currently, this window advancing test never passes until > the full TSO frame is freed up at the sender side. > > Patch coming... That was my point to Herbert, Dave - that we can't rely on Nagle - either we're triggering too early and not utilizing TSO MTU or we're triggering too late (waiting for the full TSO frame) depending on whether we use standard or TSO mss.. We need some heuristic to do partial sends under TSO. Is that what you are addressing? thanks, Nivedita