From owner-freebsd-net@FreeBSD.ORG Sun Feb 9 18:54:16 2014 Return-Path: Delivered-To: freebsd-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 ESMTPS id 75C2562D for ; Sun, 9 Feb 2014 18:54:16 +0000 (UTC) Received: from mail-yh0-x22d.google.com (mail-yh0-x22d.google.com [IPv6:2607:f8b0:4002:c01::22d]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 339901C63 for ; Sun, 9 Feb 2014 18:54:16 +0000 (UTC) Received: by mail-yh0-f45.google.com with SMTP id i57so4348638yha.32 for ; Sun, 09 Feb 2014 10:54:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=iNP4n5nZ9bWVXJSsTDTjPaWNHXg/oQVkD3JI8qQCC2U=; b=mESRvLZ8KxLXNDSV3wLhWnBqJP5iK9l+J5XdScRiI0ZUZpYTnCalu6lQuAk6s9QnK0 yC+naz43un6JMuhkcoNFtCh07Jt4GBuSZIrBQQ8S7FJPy5wh3ELipuMRv/oDlkayTSaa hckRF/uJuRft41MpaFtJS+i7LJ8BF9eYT9IKooFvVADs3GQQxgLGGe4OcQKWibAdQVBa 0wPb6WoFCQW01+0WN/vJJgTRT/oN0MyWaGf1rDgYIW9am2Aef3xZSuuCyAoniJC2RMIy yYx6cntnRtGbYsKYWHxMm0bGwsmTKJmim/cuOEZ6oFS2yl1THM5po0shBi6cKe34HxM2 QZqg== X-Received: by 10.236.51.71 with SMTP id a47mr23324582yhc.22.1391972055536; Sun, 09 Feb 2014 10:54:15 -0800 (PST) Received: from [192.168.1.76] (75-63-29-182.lightspeed.irvnca.sbcglobal.net. [75.63.29.182]) by mx.google.com with ESMTPSA id e50sm36790750yhd.26.2014.02.09.10.54.14 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 09 Feb 2014 10:54:15 -0800 (PST) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 7.1 \(1827\)) Subject: Re: Terrible NFS performance under 9.2-RELEASE? From: aurfalien In-Reply-To: Date: Sun, 9 Feb 2014 10:54:10 -0800 Content-Transfer-Encoding: 7bit Message-Id: <49357095-33DB-4881-8AC2-847C86E63350@gmail.com> References: <52DC1241.7010004@egr.msu.edu> <1629593139.16590858.1390789014324.JavaMail.root@uoguelph.ca> To: Christian Weisgerber X-Mailer: Apple Mail (2.1827) Cc: freebsd-net@freebsd.org X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.17 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, 09 Feb 2014 18:54:16 -0000 On Feb 9, 2014, at 10:03 AM, Christian Weisgerber wrote: > Rick Macklem wrote: > >> I have a "hunch" that might explain why 64K NFS reads/writes perform >> poorly for some network environments. >> A 64K NFS read reply/write request consists of a list of 34 mbufs when >> passed to TCP via sosend() and a total data length of around 65680bytes. >> Looking at a couple of drivers (virtio and ixgbe), they seem to expect >> no more than 32-33 mbufs in a list for a 65535 byte TSO xmit. I think >> (I don't have anything that does TSO to confirm this) that NFS will pass >> a list that is longer (34 plus a TCP/IP header). > > This may or may not be the same problem: > > When I switched my desktop box from FreeBSD 7 to 9, NFS read > performance from my media server (running OpenBSD) became extremely > poor. I couldn't even stream a movie any longer. Disabling TSO > on the nfe(4) interface had no effect. My workaround was to switch > from a TCP mount to a UDP one. The problem has persisted to FreeBSD 10. > > I can now report that switching to [rw]size=32768 with a TCP mount So either UDP or TCP w/rw sizes of 32K work the same? - aurf