Path: utzoo!attcan!uunet!samsung!gem.mps.ohio-state.edu!tut.cis.ohio-state.edu!pt.cs.cmu.edu!andrew.cmu.edu!zs01+ From: zs01+@andrew.cmu.edu (Zalman Stern) Newsgroups: comp.os.mach Subject: Re: References/Info on NFS ports to mach Message-ID: Date: 21 Nov 89 00:56:41 GMT References: <17098@umn-cs.CS.UMN.EDU> Organization: Information Technology Center, Carnegie Mellon, Pittsburgh, PA Lines: 19 In-Reply-To: <17098@umn-cs.CS.UMN.EDU> I'm not a Mach expert, but so far as I know, the NFS port to Mach was mostly putting vnode support in the kernel. I believe that the vnode hooks already support mmap so there shouldn't be too much magic involved. The only distributed virtual memory facilities I know of on Mach are implemented using external pagers and therefore would not involve the NFS code at all. The external pager is responsible for implementing the consistency protocol among machines. (The kernel will maintain consistency within a single machine, which may be a tightly coupled multi-processor.) If one wants to use an NFS partition as backing store for the external pager, that shouldn't be a problem since it will only happen on a single machine. If another machine wants data that has been paged onto the NFS partition, it has to go through the external pager protocol rather than NFS. Sincerely, Zalman Stern Internet: zs01+@andrew.cmu.edu Usenet: I'm soooo confused... Information Technology Center, Carnegie Mellon, Pittsburgh, PA 15213-3890