From owner-freebsd-arch@FreeBSD.ORG Sat Mar 19 23:45:34 2011 Return-Path: Delivered-To: arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E01371065672 for ; Sat, 19 Mar 2011 23:45:34 +0000 (UTC) (envelope-from nparhar@gmail.com) Received: from mail-fx0-f54.google.com (mail-fx0-f54.google.com [209.85.161.54]) by mx1.freebsd.org (Postfix) with ESMTP id 73E6F8FC08 for ; Sat, 19 Mar 2011 23:45:34 +0000 (UTC) Received: by fxm11 with SMTP id 11so5424586fxm.13 for ; Sat, 19 Mar 2011 16:45:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=H2t0wsvmInGeQ8LPJuVyI6tZFtXQEjGGHrLs/TXIZK4=; b=L+AlCk03+14ysmpVQyYKt2x2rftQjLpiMtcO5h3CW9C95tchC1hNOVlQji3LQ6pNaQ c0gHdj0/vPdlJJiiKkpY0d7yiUJAFGixP/l9UGvObZ/RY0LqU+1tInum2NChcc1gttRz BKDjJPHH6S83dB3NfTfr3A51pl/i0avZXdsIY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=qX5Q55OSIyGjdzsikrFY021/AB5ymuldEq8bqHEEmzhvpXKmljj1Ty65p957wIg81D JEaJqaPOdsS05riEkRt5plnjWuYBPjPulH299fR5d+mKbK82MLVOwcKSsXcf2Gj9cn4l C/3h1M0VX6FBL+SncSd1AsvQHygdqJcSig4cA= MIME-Version: 1.0 Received: by 10.223.76.147 with SMTP id c19mr3000014fak.55.1300576435698; Sat, 19 Mar 2011 16:13:55 -0700 (PDT) Received: by 10.223.32.204 with HTTP; Sat, 19 Mar 2011 16:13:55 -0700 (PDT) In-Reply-To: <132388F1-44D9-45C9-AE05-1799A7A2DCD9@neville-neil.com> References: <132388F1-44D9-45C9-AE05-1799A7A2DCD9@neville-neil.com> Date: Sat, 19 Mar 2011 16:13:55 -0700 Message-ID: From: Navdeep Parhar To: George Neville-Neil Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: arch@freebsd.org Subject: Re: Updating our TCP and socket sysctl values... X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 19 Mar 2011 23:45:35 -0000 On Fri, Mar 18, 2011 at 11:37 PM, George Neville-Neil wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Howdy, > > I believe it's time for us to upgrade our sysctl values for TCP sockets s= o that > they are more in line with the modern world. =A0At the moment we have the= se limits on > our buffering: > > kern.ipc.maxsockbuf: 262144 > net.inet.tcp.recvbuf_max: 262144 > net.inet.tcp.sendbuf_max: 262144 > > I believe it's time to up these values to something that's in line with h= igher speed > local networks, such as 10G. =A0Perhaps it's time to move these to 2MB in= stead of 256K. > > Thoughts? 256KB seems adequate for 10G (as long as the consumer can keep draining the socket rcv buffer fast enough). If you consider 2 x bandwidth delay product to be a reasonable socket buffer size then 256K allows for 10G networks with ~100ms delays. Normally the delay is _way_ less than this for 10G and even 256K may be an overkill (but this is ok, the kernel has tcp_do_autorcvbuf on by default) While we're here discussing defaults, what about nmbclusters and nmbjumboXX? Now those haven't kept up with modern machines (imho). Regards, Navdeep