From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 19780 invoked from network); 24 Jun 2020 18:31:50 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 24 Jun 2020 18:31:50 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id E9BDB945A6; Thu, 25 Jun 2020 04:31:41 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 4B9299459A; Thu, 25 Jun 2020 04:31:11 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=planet.nl header.i=@planet.nl header.b="V/ta9AWB"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 28E089459A; Thu, 25 Jun 2020 04:31:08 +1000 (AEST) Received: from cpsmtpb-ews03.kpnxchange.com (cpsmtpb-ews03.kpnxchange.com [213.75.39.6]) by minnie.tuhs.org (Postfix) with ESMTP id 4C75394599 for ; Thu, 25 Jun 2020 04:31:05 +1000 (AEST) Received: from cpsps-ews15.kpnxchange.com ([10.94.84.182]) by cpsmtpb-ews03.kpnxchange.com with Microsoft SMTPSVC(8.5.9600.16384); Wed, 24 Jun 2020 20:31:00 +0200 X-Brand: 7abm2Q== X-KPN-SpamVerdict: e1=0;e2=0;e3=0;e4=(e1=10;e3=10;e2=11;e4=10);EVW:Whi te;BM:NotScanned;FinalVerdict:Clean X-CMAE-Analysis: v=2.3 cv=Pv8IkzE3 c=1 sm=1 tr=0 cx=a_idp_e a=dZ5u/0G9QtS9WKCcNUBnHQ==:117 a=soxbC+bCkqwFbqeW/W/r+Q==:17 a=x1i13A_MHe4A:10 a=IkcTkHD0fZMA:10 a=nTHF0DUjJn0A:10 a=fpNhetO4AAAA:8 a=o83nqyVRAAAA:8 a=BZg3dJEvaWeIDgaC6iEA:9 a=QEXdDO2ut3YA:10 a=GIkMvKZW4Y3iu0iWrkRF:22 X-CM-AcctID: kpn@feedback.cloudmark.com Received: from smtp.kpnmail.nl ([195.121.84.13]) by cpsps-ews15.kpnxchange.com over TLS secured channel with Microsoft SMTPSVC(8.5.9600.16384); Wed, 24 Jun 2020 20:31:00 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=planet.nl; s=planet01; h=message-id:to:date:subject:mime-version:content-type:from; bh=3Tv/FbGzEcjpXw2VqObnkN8SDqhaoPYnyAFY7wQyV6M=; b=V/ta9AWBsvlqgT3PMxhQUWxeicnESg/lz2EgiOo8+o5jz7NteGd5KUBhiYc8kIefpDWkC1hyMDkNg habPrW60S8NYploZbQbul2fd8pDEKR44Nyso9T2VADCC8g2heTxqSXokthaBUXmIpy5H9pkvAkcplg +itvYTy2Wuyg+Qvs= X-KPN-VerifiedSender: Yes X-CMASSUN: 33|dYog0quiQ21CqKaRRz6JN1uU0EjgLklMohVS73mL+hyy8We/t+z1esFOBF+6pYT E4eNqZsVXA93Kr+POrT1/ew== X-Originating-IP: 80.101.112.122 Received: from mba2.fritz.box (sqlite.xs4all.nl [80.101.112.122]) by smtp.kpnmail.nl (Halon) with ESMTPSA id da381cab-b648-11ea-a078-005056998788; Wed, 24 Jun 2020 20:31:00 +0200 (CEST) From: Paul Ruizendaal Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Date: Wed, 24 Jun 2020 20:31:00 +0200 References: <4FC7FA55-5035-41A2-B52F-AE26DC8BED2C@planet.nl> <20200624165107.GA5737@alice> To: Anthony Martin , TUHS main list In-Reply-To: <20200624165107.GA5737@alice> Message-Id: <17CD58F0-2474-4308-86BA-C8847D7ABA21@planet.nl> X-Mailer: Apple Mail (2.3445.104.11) X-OriginalArrivalTime: 24 Jun 2020 18:31:00.0674 (UTC) FILETIME=[9C2AE220:01D64A55] X-RcptDomain: minnie.tuhs.org Subject: Re: [TUHS] VFS prior to 1984 X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" On 24 Jun 2020, at 18:51, Anthony Martin wrote: >=20 > Paul Ruizendaal once said: >> When googling for File System Switch or Virtual File System most = sources >> mention Sun NFS and SysVr3 as the earliest implementations. Some = sources >> mention 8th Edition. >>=20 >> I did a (short) search on FSS/VFS in earlier, non-Unix OS=E2=80=99s = (Tenex, >> Multics, CTSS, etc.), but none of those seem to have had a comparable >> concept. >>=20 >> Does anybody recall prior art (prior to 1984) in this area? >=20 > The concept of the "remote inode" was introduced in: >=20 > Luderer, G. W., Che, H., Haggerty, J. P., Kirslis, P. A., & Marshall, > W. T. (1981). A distributed UNIX system based on a virtual circuit > switch. ACM SIGOPS Operating Systems Review, 15(5), 160-168. > The only other prior art I know of is >=20 > Toda, I. W. A. O. (1980). DCNA higher level protocols. IEEE > Transactions on Communications, 28(4), 575-584. >=20 > wherein they state the following: >=20 > A virtual file system, from the viewpoint of application programs on = a > computer, models the file system functions of other computers. This = is > done in the same way as with virtual terminals, a virtual file system > consists of a UPP having virtual files (VF), and a UCP which executes > virtual file system protocols. Thanks for those pointers: I had not thought to include distributed = systems in my initial search. Clem also pointed out LOCUS in this area. = It would seem that S/F-Unix (the Luderer paper) and LOCUS happened at = about the same time and both have the concept of a remote inode. The Luderer paper has only a few details about implementation and = besides describing the remote inode concept they mention: =E2=80=9COf 27 system call types related to files, 18 result in message = traffic if remote files are involved. Of these, 10 contain a path name = as an argument, and the remaining 8 refer to already opened files. Path = names or the data read or written can be up to 64K bytes long. The = structure of each message is a type code followed by type-dependent = data.=E2=80=9D In a way, the approach resembles the system call forwarding that Heinz = Lycklama did for his 'satellite systems' work. I asked Bill Marshall (one of the S/F co-authors) about it a few months = ago and he recalls that they ran into problems with corner case = semantics in their implementation, and that Peter Weinberger later = approached the issue afresh 'thinking about the hard cases first.' Bill = does not have S/F-Unix source code, and I have not been able to contact = Gottfried Luderer yet. I have not yet been able to look at the DCNA paper yet. > I'd be interested if you find anything earlier. I came across this 1979 paper by P.M. Lu from Bell Labs Naperville https://ieeexplore.ieee.org/document/762533 The abstract says: "RIDE (Resource-Sharing in a Distributed Environment) has been designed = and implemented for the UNIX operating system to provide sharing of = remote files, remote process invocation and interprocess communication = in a distributed computing environment. The system is designed to = support a uniform interface for both local and remote access in a = network. The user programs can be executed in a single or multiple = machine environment without any program modification.=E2=80=9D I do not know what RIDE was and if its approach qualifies as a FSS = precursor. Maybe it is like 'Unix United / Newcastle Connection' in its = approach. It does seem an interesting paper in any case, as its front page = includes: 'This system was designed to replace the network interface = programs that previously operated on the SPIDER system.'