From owner-freebsd-current@FreeBSD.ORG Mon Nov 19 00:04:26 2007 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 1507C16A421 for ; Mon, 19 Nov 2007 00:04:26 +0000 (UTC) (envelope-from jfvogel@gmail.com) Received: from nf-out-0910.google.com (nf-out-0910.google.com [64.233.182.190]) by mx1.freebsd.org (Postfix) with ESMTP id 95E9213C45A for ; Mon, 19 Nov 2007 00:04:25 +0000 (UTC) (envelope-from jfvogel@gmail.com) Received: by nf-out-0910.google.com with SMTP id b2so1257711nfb for ; Sun, 18 Nov 2007 16:04:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=8XzGd8c69+bnOH4xxj1AT+4HGDtnxf7PtgWoMabmN1s=; b=f3tnG6lkIKxkOY7BFOOrYiW5iM/BQwOWDl4v9rp8l+6MagyqiZ4Xb/cs8sX1Wa+w8NLeovvIB+UdRmiBCz/W0OYI5b7bpJMfK2XYJNudxYQW9w/Vjn7ArmtvJEXPJM0AAKrJZap/FsMOMLxTLParKOf1VMvpab8CwO9QY36bV20= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Sotb3oHuNSFUG6xzput94F3PipLTPe/1WA2terkJgC5EA2Q3PrC5cFN5fcaXmlqQQw2omboXcjkgALFkrWy6mDj22YkASlt2rR86I6GtOMOYsGs/+TGH1g+EMzvTK2MXR7rMj8GMRVySrk98xcEoOAsGE/MUJMQItwWev40moUg= Received: by 10.86.68.20 with SMTP id q20mr971447fga.1195430654955; Sun, 18 Nov 2007 16:04:14 -0800 (PST) Received: by 10.86.100.19 with HTTP; Sun, 18 Nov 2007 16:04:14 -0800 (PST) Message-ID: <2a41acea0711181604p7a58df5chdae6a98f915dcb99@mail.gmail.com> Date: Sun, 18 Nov 2007 16:04:14 -0800 From: "Jack Vogel" To: pyunyh@gmail.com In-Reply-To: <20071118054409.GA1044@cdnetworks.co.kr> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20071117003504.R31357@mindcrime.int.bit0.com> <20071117170537.F59492@mindcrime.int.bit0.com> <20071117182232.T59492@mindcrime.int.bit0.com> <473F9552.50402@bit0.com> <473FBD1A.8010207@bit0.com> <20071118054409.GA1044@cdnetworks.co.kr> Cc: Mike Silbersack , Andre Oppermann , Kip Macy , Denis Shaposhnikov , freebsd-current@freebsd.org, Mike Andrews Subject: Re: bizarre em + TSO + MSS issue in RELENG_7 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Nov 2007 00:04:26 -0000 On Nov 17, 2007 9:44 PM, Pyun YongHyeon wrote: > > It seems that em(4) uses EM_TSO_SIZE(64K) to create DMA tag. A packet > can have 64K payload under TSO so its the mximum size of the mbuf > chain would be 64K + sizeof(link layer). So I guess the EM_TSO_SIZE > should be increased to hold sizeof(link layer). > It had been a long time since I looked into em(4) so I'm not sure. Hmm, you are right about this Pyun, I think this should be fixed, although I do not see how that would effect this since Mike's payloads are always way under this. Still I'll keep this in mind to be changed. Thanks for pointing it out. Jack