From owner-freebsd-net@FreeBSD.ORG Mon Aug 20 21:09:01 2007 Return-Path: Delivered-To: net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8B8D616A420 for ; Mon, 20 Aug 2007 21:09:01 +0000 (UTC) (envelope-from SRS0=51c1414937382bb93b9c640e934c9ada58ae09d2=433=es.net=oberman@es.net) Received: from postal1.es.net (postal2.es.net [IPv6:2001:400:14:3::7]) by mx1.freebsd.org (Postfix) with ESMTP id 47FF713C46A for ; Mon, 20 Aug 2007 21:08:59 +0000 (UTC) (envelope-from SRS0=51c1414937382bb93b9c640e934c9ada58ae09d2=433=es.net=oberman@es.net) Received: from ptavv.es.net (ptavv.es.net [198.128.4.29]) by postal2.es.net (Postal Node 2) with ESMTP (SSL) id ZDC55958; Mon, 20 Aug 2007 14:08:58 -0700 Received: from ptavv.es.net (ptavv.es.net [127.0.0.1]) by ptavv.es.net (Tachyon Server) with ESMTP id 326AE4506A; Mon, 20 Aug 2007 14:08:58 -0700 (PDT) To: net@freebsd.org Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1187644138_93167P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Mon, 20 Aug 2007 14:08:58 -0700 From: "Kevin Oberman" Message-Id: <20070820210858.326AE4506A@ptavv.es.net> Cc: andre@networx.ch Subject: Unable to set socket size > 16MB 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: Mon, 20 Aug 2007 21:09:01 -0000 --==_Exmh_1187644138_93167P Content-Type: text/plain; charset=us-ascii Content-Disposition: inline I am trying to tune a FreeBSD system for ~100 ms. RTT at 10 Gbps. (I posted another message about this back on 8/17). I am running current of late July 31. I am using iperf and I have confirmed (with gdb) that it is passing setsockopt a size of 67108864 and setsockopt is returning 0. When I capture the SYN packets, I am seeing a window of 64K and a scale factor of 8. For 64 MB, the scale factor should be 10. Is there some hidden limitation that would restrict this or is there a bug involved? I have set net.inet.tcp.(send|recv)space to 64m. kern.ipc.maxsockbuf=134217728. Here is the 3-way handshake: 13:57:45.571614 IP lbl.52460 > perf-bnl.commplex-link: S 4070670678:4070670678(0) win 65535 13:57:45.665645 IP perf-bnl.commplex-link > lbl.52460: S 3909263475:3909263475(0) ack 4070670679 win 65535 13:57:45.665683 IP lbl.52460 > perf-bnl.commplex-link: . ack 1 win 65535 Any reason for this? Any workaround or fix? Or am I missing something? -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751 --==_Exmh_1187644138_93167P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (FreeBSD) Comment: Exmh version 2.5 06/03/2002 iD8DBQFGygLqkn3rs5h7N1ERAvZCAJ91VskviFrSx8/gzotJauX1QHhV8gCeMv6v +EeYwYXLmnA/y7ofsCB1odE= =lrH3 -----END PGP SIGNATURE----- --==_Exmh_1187644138_93167P--