Path: utzoo!utgpu!watserv1!watmath!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!caen!ox.com!ox.com!emv From: emv@ox.com (Ed Vielmetti) Newsgroups: comp.protocols.nfs Subject: Re: Symlink locking considered useless over NFS Message-ID: Date: 25 Apr 91 19:09:38 GMT References: <3064@cirrusl.UUCP> <280EE8A1.30D@tct.com> <99526@sgi.sgi.com> Sender: usenet@ox.com (Usenet News Administrator) Organization: OTA Limited Partnership, Ann Arbor MI. Lines: 41 In-Reply-To: vjs@rhyolite.wpd.sgi.com's message of 25 Apr 91 04:44:46 GMT In article <99526@sgi.sgi.com> vjs@rhyolite.wpd.sgi.com (Vernon Schryver) writes: The big problem with NFS/TCP still seems to me that it won't scale as well as NFS/UDP. well, there are lots of things that could need to be scaled up -- number of connections to a server. NFS/UDP wins here in your analysis, or put another way there really isn't any obviously good way to have 1000 hosts all talking directly to the same machine even though that machine may be fast enough. speed of transfer on fast networks. NFS/TCP wins here because it's easier to get a good TCP on FDDI-class nets than it is to get similar performance out of UDP. (!?) There are other speed issues here that are more implementation sensitive. distance from client to server where this measures some combination of packet loss, round-trip time and variability, and other network nasties. NFS/TCP wins because it can't hardly help but being better than current NFS/UDP implementations, and because more work has been done in getting TCP performance to be good on wide-area nets. is this a fair assessment? for myself, the "scaling" i'd like to see is over wide area networks; for that purpose NFS/TCP looks quite reasonable. i wonder whether it'll be real enough in time to compete for attention with the other reasonable wide-area file service (Transarc's AFS). -- Msen Edward Vielmetti /|--- moderator, comp.archives emv@msen.com "(6) The Plan shall identify how agencies and departments can collaborate to ... expand efforts to improve, document, and evaluate unclassified public-domain software developed by federally-funded researchers and other software, including federally-funded educational and training software; " High-Performance Computing Act of 1991, S. 218