From owner-freebsd-current@FreeBSD.ORG Thu Aug 28 05:57:02 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1610016A4BF for ; Thu, 28 Aug 2003 05:57:02 -0700 (PDT) Received: from dfmm.org (walter.dfmm.org [209.151.233.240]) by mx1.FreeBSD.org (Postfix) with ESMTP id 68A3143FFD for ; Thu, 28 Aug 2003 05:57:01 -0700 (PDT) (envelope-from freebsd-current@dfmm.org) Received: (qmail 75025 invoked by uid 1000); 28 Aug 2003 12:57:00 -0000 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 28 Aug 2003 12:57:00 -0000 Date: Thu, 28 Aug 2003 05:57:00 -0700 (PDT) From: Jason Stone X-X-Sender: jason@walter To: freebsd-current@freebsd.org In-Reply-To: <3F4DCBB1.2BDA25AC@mindspring.com> Message-ID: <20030828055145.P3417@walter> References: <20030827211535.N3417@walter> <3F4DCBB1.2BDA25AC@mindspring.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Subject: Re: nfs tranfers hang in state getblck or nfsread X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Aug 2003 12:57:02 -0000 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 > > I'm also seeing a similar problem - I have a cluster of high-volume > > mailservers delivering mail over nfs to maildirs on a netapp. The cluster > > was all 4-stable, but I decided to mix a couple of 5.1 boxes in to see how > > they would do. [...] > > My mounts are all nfsv3 over udp. > > UDP has problems, if you lose any packets at all. The problem is that > the packet reassembly buffer stays full until you retry, and the retry > is out of band, for packets larger than the MTU size. > > What happens when you drop the read and write size low enough that the > data and headers fit in a single UDP packet (e.g. according to > "tcpdump")? Does it "suddenly" become more reliable? I'll try to play around with it and see. We actually had this discussion already over on -performance (and I get what you're saying), but the interesting question here is, why is 5.1 behaving so differently from 4-stable on identical hardware under identical load. -Jason -------------------------------------------------------------------------- Freud himself was a bit of a cold fish, and one cannot avoid the suspicion that he was insufficiently fondled when he was an infant. -- Ashley Montagu -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (FreeBSD) Comment: See https://private.idealab.com/public/jason/jason.gpg iD8DBQE/TfwcswXMWWtptckRAoZIAKCA6doHe3VXrwFj/xX/HkfV18emYACfW1GK Yw5ZniWoHqHQg/ez8sj4Svc= =hFfm -----END PGP SIGNATURE-----