Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751914Ab0HVHjH (ORCPT ); Sun, 22 Aug 2010 03:39:07 -0400 Received: from mail-vw0-f46.google.com ([209.85.212.46]:49788 "EHLO mail-vw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751286Ab0HVHjE convert rfc822-to-8bit (ORCPT ); Sun, 22 Aug 2010 03:39:04 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=Jw+UOHu2v3Jfpni/yLY1kvuPY6/36GbdOFNkmwQ42/y6AveWzBxSaXOeXxqDimlPdY vDAB5nbIQwgD7+3c3QaC7esZ9bea3EAZi0Yb2yotyVOMVSwdONsHt8ya94NIARCUhjBZ Zf8Z5aePDMr8UtNdNg/1t3EarbX8ewD1S7UG4= MIME-Version: 1.0 In-Reply-To: <1282423398.3015.39.camel@mulgrave.site> References: <594039.74663.qm@web111905.mail.gq1.yahoo.com> <1282144271.3035.31.camel@mulgrave.site> <1282148296.3035.49.camel@mulgrave.site> <4C6C1D70.7020502@vlnb.net> <41A1E2691BBB412BADCDE5F515CD8EDA@usish.com.cn> <8A96806D-6CD7-44AD-8A9D-143C098C95A4@uni-paderborn.de> <1282256949.30453.278.camel@haakon2.linux-iscsi.org> <4C701E08.2020005@vlnb.net> <1282423398.3015.39.camel@mulgrave.site> Date: Sun, 22 Aug 2010 09:39:03 +0200 X-Google-Sender-Auth: OS5nWxhkX8cnkIlHfaoi6LpKjec Message-ID: Subject: Re: [Scst-devel] Fwd: Re: linuxcon 2010... From: Bart Van Assche To: James Bottomley Cc: Vladislav Bolkhovitin , Dirk Meister , linux-scsi@vger.kernel.org, Chetan Loke , Chetan Loke , scst-devel , linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1664 Lines: 38 On Sat, Aug 21, 2010 at 10:43 PM, James Bottomley wrote: > On Sat, 2010-08-21 at 22:42 +0400, Vladislav Bolkhovitin wrote: >> [ ... ] >> >> You forgot to mention one small thing. You are going to (re)use current >> STGT interface for user space backend, which in 5 years of being >> mainline has not gained any noticeable interest, because it is >> fundamentally slow. > > That's not exactly what the results of a speed comparison one of your > people did said, now is it? ?The results were actually not much > difference on line speeds up to GigE. > > [ ... ] I assume that you are referring to this message: http://lkml.org/lkml/2008/1/29/387 ? You might have missed the reply that was posted by Roland Dreier, a highly regarded kernel maintainer and InfiniBand expert (http://lkml.org/lkml/2008/1/29/402): "Maybe I'm all wet, but I think iSER vs. SRP should be roughly comparable. The exact formatting of various messages etc. is different but the data path using RDMA is pretty much identical. So the big difference between STGT iSER and SCST SRP hints at some big difference in the efficiency of the two implementations." Furthermore, I would like to clarify that Vlad hasn't asked me to start working on the SCST project but that I selected the SCST project myself after an extensive stability and performance comparison of four existing open source storage target projects. Bart. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/