From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759987AbYDXNGk (ORCPT ); Thu, 24 Apr 2008 09:06:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754063AbYDXNGS (ORCPT ); Thu, 24 Apr 2008 09:06:18 -0400 Received: from fg-out-1718.google.com ([72.14.220.158]:60560 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752589AbYDXNGO (ORCPT ); Thu, 24 Apr 2008 09:06:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=QhHAneTE2jUapwXTXgSlZxl3nhRCs6mB6hBbqgB0lrQHSgAR3cv1fsbXPDnu5trKmqZQx2ZUjwsCTaImM3GJbHk+Zspw5CKlNiWzk+/33DtxTtpbCEF9A0kUslkzKlVZjbkoJ7Ntj39d0JV0TFIdCtuggrws0DgDDr5EVCxvlUA= Message-ID: <18b669d80804240606n47854939x94278f8d974034c1@mail.gmail.com> Date: Thu, 24 Apr 2008 22:06:11 +0900 From: "Shigeo N" To: "Andi Kleen" Subject: Re: XTP for 2.6.25 Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org In-Reply-To: <873apbijb9.fsf@basil.nowhere.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <18b669d80804240314t7b2f6e4cpc9a9f2690c6d21b4@mail.gmail.com> <873apbijb9.fsf@basil.nowhere.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now I have connected 2 hosts directly, and evaluate the each throughput. Then all the results of UDP, TCP and XTP are the same and 94Mbps. (My netwrok is 100Base/TX). In this case round-trip time between 2 hosts is less than 0.1ms because they are directly connected. But my previouse case, round-trip time between 2 hosts are 4ms. (I use IPSEC between the security gateways to increase delay). I think that's the reason TCP throughput is slow. If ACK packets are delayed, sending window cannot slide and sending packets cannot be fully bursted. If I changes wmem size through /proc/sys/net/ipv4/tcp_wmem, TCP's throughput may improve, but congestion control becomes more difficult for TCP. That is TCP's disadvantage to XTP. Best Shigeo On 4/24/08, Andi Kleen wrote: > "Shigeo N" writes: > > > > I tested in the network where UDP throughput is 29Mbps, then TCP > > throughput was 13Mbps, but XTP's reached to 25Mbps. > > One interesting question is why TCP was so much slower than UDP > on your test. It shouldn't be on a fair test setup. > > Please post details. Was the network losing packets? > > New protocols might be interesting, but even more interesting is to > fix any (real) problems in existing protocols. > > -Andi >