From owner-freebsd-arch@FreeBSD.ORG Sun Mar 20 03:47:31 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 6E0F3106564A for ; Sun, 20 Mar 2011 03:47:31 +0000 (UTC) (envelope-from gnn@neville-neil.com) Received: from vps.hungerhost.com (vps.hungerhost.com [216.38.53.176]) by mx1.freebsd.org (Postfix) with ESMTP id 467B78FC13 for ; Sun, 20 Mar 2011 03:47:31 +0000 (UTC) Received: from 197.214.32.202.bf.2iij.net ([202.32.214.197] helo=[192.168.12.144]) by vps.hungerhost.com with esmtpsa (TLSv1:AES128-SHA:128) (Exim 4.69) (envelope-from ) id 1Q19c2-0006KW-ES; Sat, 19 Mar 2011 23:47:31 -0400 Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: text/plain; charset=us-ascii From: George Neville-Neil In-Reply-To: Date: Sun, 20 Mar 2011 12:47:27 +0900 Content-Transfer-Encoding: quoted-printable Message-Id: <281E39E0-55D0-4B52-9CD9-F437442B67EC@neville-neil.com> References: <132388F1-44D9-45C9-AE05-1799A7A2DCD9@neville-neil.com> To: Navdeep Parhar X-Pgp-Agent: GPGMail 1.3.2 X-Mailer: Apple Mail (2.1082) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - vps.hungerhost.com X-AntiAbuse: Original Domain - freebsd.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - neville-neil.com 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: Sun, 20 Mar 2011 03:47:31 -0000 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Mar 20, 2011, at 08:13 , Navdeep Parhar wrote: > On Fri, Mar 18, 2011 at 11:37 PM, George Neville-Neil > wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >>=20 >> Howdy, >>=20 >> I believe it's time for us to upgrade our sysctl values for TCP = sockets so that >> they are more in line with the modern world. At the moment we have = these limits on >> our buffering: >>=20 >> kern.ipc.maxsockbuf: 262144 >> net.inet.tcp.recvbuf_max: 262144 >> net.inet.tcp.sendbuf_max: 262144 >>=20 >> I believe it's time to up these values to something that's in line = with higher speed >> local networks, such as 10G. Perhaps it's time to move these to 2MB = instead of 256K. >>=20 >> Thoughts? >=20 > 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) >=20 > While we're here discussing defaults, what about nmbclusters and > nmbjumboXX? Now those haven't kept up with modern machines (imho). >=20 Yes we should also up the nmbclusters, IMHO, but I wasn't going to put that in the same bucket with the TCP buffers just yet. On 64 bit/large memory machines you could make the nmbclusters far higher than our current default. I know people who just set that to 1,000,000 by default. If people are also happy to up nmbclusters I'm willing to conflate that with this. Best, George -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (Darwin) iEYEARECAAYFAk2FeM8ACgkQYdh2wUQKM9KPZgCgy9AcsoowTLk+sAaFHx52VSkW mGEAn22eOTi3yqweMrOKsVkZ2XOWi9kX =3D22fZ -----END PGP SIGNATURE-----