From owner-freebsd-net@FreeBSD.ORG Sun Mar 11 06:24:22 2007 Return-Path: X-Original-To: net@freebsd.org Delivered-To: freebsd-net@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 932E916A400 for ; Sun, 11 Mar 2007 06:24:22 +0000 (UTC) (envelope-from keith.arner@gmail.com) Received: from mu-out-0910.google.com (mu-out-0910.google.com [209.85.134.185]) by mx1.freebsd.org (Postfix) with ESMTP id 1444F13C442 for ; Sun, 11 Mar 2007 06:24:21 +0000 (UTC) (envelope-from keith.arner@gmail.com) Received: by mu-out-0910.google.com with SMTP id g7so1595010muf for ; Sat, 10 Mar 2007 22:24:20 -0800 (PST) DKIM-Signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:references:x-google-sender-auth; b=Vsf8Yx32Ca04RWWQPWi9trS6JjOG2bUkxDi3IpwbcI4X7nWAMUU8kB1hE/9SzSWuD3csYozmVUW6CWqEb7gIfzlulcnAof7Kci8Up+qQ95hJlWtBsUU2MvPe0bqQD22u8IY3/x2jS8/1AqaDlqEfB1FrJUQnzS0nTMfy7Mx/LW8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:references:x-google-sender-auth; b=tZuKvl3UANCsyua2zvNsCiQS2wH/EeQUvmS084mBhu7csEPT0+Ijdj/kLnCCxF/V3miX9rWnz1dEddZ3mjTLknHO/X8YNPz4P6pxIspALaCH5vBrTZokq4CoU77eM4QQtgygOwNAn8IV+DD5dk+JIpJFGdyBLT+YNWLsx0ctrhQ= Received: by 10.82.152.16 with SMTP id z16mr5871852bud.1173592675302; Sat, 10 Mar 2007 21:57:55 -0800 (PST) Received: by 10.82.121.1 with HTTP; Sat, 10 Mar 2007 21:57:55 -0800 (PST) Message-ID: <8e552a500703102157p1845926au65bb3adaf81c01c0@mail.gmail.com> Date: Sun, 11 Mar 2007 00:57:55 -0500 From: "Keith Arner" Sender: keith.arner@gmail.com To: "Robert Watson" In-Reply-To: <20070310035135.B30274@fledge.watson.org> MIME-Version: 1.0 References: <45C0CA5D.5090903@incunabulum.net> <45E6BEE0.2050307@FreeBSD.org> <45E6C22D.7060200@freebsd.org> <45E6D70C.10104@FreeBSD.org> <45EEB086.3050409@FreeBSD.org> <45F03269.7050705@FreeBSD.org> <45F08F1D.5080708@us.fujitsu.com> <20070310035135.B30274@fledge.watson.org> X-Google-Sender-Auth: 7cfc9a9f48ac426b Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: Dave Baukus , net@freebsd.org Subject: Re: netisr_direct X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 11 Mar 2007 06:24:22 -0000 On 3/9/07, Robert Watson wrote: > It also introduces > parallelism in the in-bound network layer processing path by allowing > processing to occur in more than one thread at a time. However, you can > see >From the experimentation I've done, it seems that for TCP loads at least, the input path tends to bottleneck on INP_INFO_WLOCK(&tcbinfo), essentially reducing the input path to a single thread. reduced parallelism in some environments as the ithread no longer run > concurrently with the netisr. I would not use net.isr.direct in versions > of > FreeBSD before 6.1, but it should be pretty safe for 6.1 and later. > Admitedly, the experimentation I've done has been with 6.0, rather than 6.1. Have there been any changes in 6.1 that address the locking in the TCP input path? I'm very interested in being able to run highly parallel TCP loads. Keith