From owner-freebsd-net@FreeBSD.ORG Wed Aug 14 19:40:20 2013 Return-Path: Delivered-To: net@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 63A24CC2 for ; Wed, 14 Aug 2013 19:40:20 +0000 (UTC) (envelope-from peter@wemm.org) Received: from mail-ve0-x22e.google.com (mail-ve0-x22e.google.com [IPv6:2607:f8b0:400c:c01::22e]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 1D1C4218E for ; Wed, 14 Aug 2013 19:40:20 +0000 (UTC) Received: by mail-ve0-f174.google.com with SMTP id d10so8123066vea.33 for ; Wed, 14 Aug 2013 12:40:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wemm.org; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=6zFjB2bwhY+4R1Qst7mshCrVIjcM2qxRAu9JGhFOIhE=; b=DXO+hkLL/EUUfR8iO3wMDfp/FkWwI5YSx64qsMR4kiHymH1Kexb9j3zb/yEQOvcgrk lkkL+FQKsfEDTWhf4pJM5NX9MSEGkd8iXrTjJMHYrx7W5gZpHphOo3gr/M4K5iLIRTs8 2xtq7KEi9uq/XO1DqIFdVbMf6r1o4Nr5YrEoA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=6zFjB2bwhY+4R1Qst7mshCrVIjcM2qxRAu9JGhFOIhE=; b=dLJzfZkuCKpH8wmfpGgVgF4hmuwN269e+hYl5P+EujruB1dGRG5HkkiPyHmO/MpBaD geFOtZNw7BErwYZyWdlpNiSIChfpCMRIsSFqmHPglWsUaGW/YFTAGUStsbipiLrTo1K/ Hg3PqEAXHNeElCgJUq2aJ1Zm+GlilmLWuw2hvNTmTnf9gEe4Swa8HIwpj35eOMZQR/s8 fLvSp2eZkUvvdBZsW9pLCzVRh0MyE2cR76NII2nS/NVewdGZ9U2kH5ZECWsU4qqGdbXB zPsYZ84DRoMkW0ORAVEDy/j+KFyWZxE9oRQaXhquLGGfgqhrrJicKiwfCP4L1kV5r//t a15Q== X-Gm-Message-State: ALoCoQmtHPOw68jh4Na0fIQGdrx/WBjqLeF8s5OJs1wev0PRu6rkV+CR/3TPeiai4ZXWkw3RlWNh MIME-Version: 1.0 X-Received: by 10.220.50.10 with SMTP id x10mr599307vcf.86.1376509219229; Wed, 14 Aug 2013 12:40:19 -0700 (PDT) Received: by 10.220.167.74 with HTTP; Wed, 14 Aug 2013 12:40:19 -0700 (PDT) In-Reply-To: References: <520A6D07.5080106@freebsd.org> <520AFBE8.1090109@freebsd.org> <520B24A0.4000706@freebsd.org> <520B3056.1000804@freebsd.org> <20130814102109.GA63246@onelab2.iet.unipi.it> <587579055.20130814154713@serebryakov.spb.ru> Date: Wed, 14 Aug 2013 12:40:19 -0700 Message-ID: Subject: Re: it's the output, not ack coalescing (Re: TSO and FreeBSD vs Linux) From: Peter Wemm To: Adrian Chadd Content-Type: text/plain; charset=ISO-8859-1 Cc: Lawrence Stewart , Lev Serebryakov , Luigi Rizzo , FreeBSD Net X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Aug 2013 19:40:20 -0000 On Wed, Aug 14, 2013 at 11:11 AM, Adrian Chadd wrote: > On 14 August 2013 04:47, Lev Serebryakov wrote: > > >> And we should invalidate this info on ARP/route changes, or connection >> will be lost in such cases, am I right?.. So, on each such event code >> should look into all sockets and check, if routing/ARP information is >> still >> valid for them. Or we should store lists of sockets in routing and ARP >> tables... I don't know, what is worse. >> > > .. or per-CPU copies of the ARP table.. ? Local cache at each consumer and check a generation number to see if it needs to be re-validated before using. The obvious problem with this though is that big networks tend to kill your caches. -- Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com; KI6FJV UTF-8: for when a ' just won\342\200\231t do. ZFS must be the bacon of file systems. "everything's better with ZFS"