From owner-svn-src-all@FreeBSD.ORG Mon Aug 19 17:33:06 2013 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id A407E2C8; Mon, 19 Aug 2013 17:33:06 +0000 (UTC) (envelope-from nparhar@gmail.com) Received: from mail-pa0-x233.google.com (mail-pa0-x233.google.com [IPv6:2607:f8b0:400e:c03::233]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 6C3ED2CCA; Mon, 19 Aug 2013 17:33:06 +0000 (UTC) Received: by mail-pa0-f51.google.com with SMTP id lf1so4891675pab.10 for ; Mon, 19 Aug 2013 10:33:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=m4jqV48frauhdoi402GQZ01mWn62cuorOFwNNL8c9zM=; b=tO+cF5lWzKlIWQsqm8r2ROJJCkQ8yaQmJcWDRPF0dHpbxDNz0bccC/noxyUkcxTsCt 09ChQA9WDS3Aszr+Rr3R9tjbnpCB39w9mq90qv+5RX5tF/Mszqq0ckHcOql5T5qHSu1L naV7zg45VJOkhtzNGXRUOQe7pHmujbEvu9glv8nyiwiRiC0pIriKTyxF+8oP4Jgq7/Cq A/BInIaW/CA5pruRAA+fh5hhUynaUF/t4vraz9I4wR6wL0lYHHy6cIufRdjj+GCWbO+H rqHqwYvaSrLMVm0Ig1hjP7gLSbNMHs1kpeGuwkGwYjSvhTSzZIZ6tJ1/Uxe1o+20jf/Y K0sg== X-Received: by 10.66.171.13 with SMTP id aq13mr5684391pac.30.1376933586128; Mon, 19 Aug 2013 10:33:06 -0700 (PDT) Received: from [10.192.166.0] (stargate.chelsio.com. [67.207.112.58]) by mx.google.com with ESMTPSA id nj9sm16325367pbc.13.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 19 Aug 2013 10:33:04 -0700 (PDT) Sender: Navdeep Parhar Message-ID: <521256CE.6070706@FreeBSD.org> Date: Mon, 19 Aug 2013 10:33:02 -0700 From: Navdeep Parhar User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:17.0) Gecko/20130819 Thunderbird/17.0.8 MIME-Version: 1.0 To: Andre Oppermann Subject: Re: svn commit: r254520 - in head/sys: kern sys References: <201308191116.r7JBGsc6065793@svn.freebsd.org> In-Reply-To: <201308191116.r7JBGsc6065793@svn.freebsd.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Aug 2013 17:33:06 -0000 On 08/19/13 04:16, Andre Oppermann wrote: > Author: andre > Date: Mon Aug 19 11:16:53 2013 > New Revision: 254520 > URL: http://svnweb.freebsd.org/changeset/base/254520 > > Log: > Remove the unused M_NOFREE mbuf flag. It didn't have any in-tree users > for a very long time, if ever. > > Should such a functionality ever be needed again the appropriate and > much better way to do it is through a custom EXT_SOMETHING external mbuf > type together with a dedicated *ext_free function. > > Discussed with: trociny, glebius > > Modified: > head/sys/kern/kern_mbuf.c > head/sys/kern/uipc_mbuf.c > head/sys/sys/mbuf.h > Hello Andre, Is this just garbage collection or is there some other reason for this? I recently tried some experiments to reduce the number of mbuf and cluster allocations in a 40G NIC driver. M_NOFREE and EXT_EXTREF proved very useful and the code changes to the kernel were minimal. See user/np/cxl_tuning. The experiment was quite successful and I was planning to bring in most of those changes to HEAD. I was hoping to get some runtime mileage on the approach in general before tweaking the ctors/dtors for jumpbo, jumbo9, jumbo16 to allow for an mbuf+refcnt within the cluster. But now M_NOFREE has vanished without a warning... Regards, Navdeep