From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752253Ab1HYErU (ORCPT ); Thu, 25 Aug 2011 00:47:20 -0400 Received: from mx02.ctc-g.co.jp ([131.248.58.2]:50667 "EHLO mx-s.ctc.ctc-g.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752135Ab1HYErS (ORCPT ); Thu, 25 Aug 2011 00:47:18 -0400 Date: Thu, 25 Aug 2011 13:46:58 +0900 From: "Jun.Kondo" Subject: Re: [omega-g1:11110] Re: [PATCH] net: configurable sysctl parameter "net.core.tcp_lowat" for sk_stream_min_wspace() In-reply-to: <20110822.113544.28950168095176936.davem@davemloft.net> To: David Miller Cc: linux-kernel@vger.kernel.org, omega-g1@ctc-g.co.jp, notsuki@redhat.com, motokazu.kozaki@hp.com, htaira@redhat.com, netdev@vger.kernel.org, tomohiko.takahashi@ctc-g.co.jp, kotaro.sakai@ctc-g.co.jp, ken.sugawara@ctc-g.co.jp Reply-to: jun.kondo@ctc-g.co.jp Message-id: <4E55D3C2.40308@ctc-g.co.jp> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit X-post-Received: by post02.ctc-g.co.jp (CTC-GN 2006/10/01) id 741DE74EE; Thu, 25 Aug 2011 13:46:56 +0900 (JST) X-vs: by localhost.is02.ctc-g.co.jp (CTC-GN mail 2009/02/01) id 5D96153E5F; Thu, 25 Aug 2011 13:46:56 +0900 (JST) X-vs: by is02.ctc-g.co.jp (CTC-GN mail 2009/02/01) id 55A0B53E5E; Thu, 25 Aug 2011 13:46:56 +0900 (JST) References: <4E4E2CCD.6050809@ctc-g.co.jp> <20110819.024326.598275465899000817.davem@davemloft.net> <4E51A3F0.5010500@ctc-g.co.jp> <20110822.113544.28950168095176936.davem@davemloft.net> User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; ja; rv:1.9.2.12) Gecko/20101027 Thunderbird/3.1.6 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, once the transmission buffer becomes full, it is not possible to write again unless there is one third of free space in the transmission buffer. Our modification request is not intending to change the behavior of the OS itself, but making the value "one third" to be configurable, not fixed. Thus it would be still possible to set the value to 1/3. So, could you please tell us why it is not acceptable to make it configurable, and what is the persistence with the value of 1/3?