Subject: FORW: Re: mmap and NFS
To: None <tech-kern@NetBSD.ORG>
From: Jason Thorpe <>
List: tech-kern
Date: 08/08/1996 09:37:49
Saw this go across freebsd-hackers ... someone might be interested :-)

------- Forwarded Message

From: "Ron G. Minnich" <rminnich@Sarnoff.COM>
To: FreeBSD hackers <freebsd-hackers@FreeBSD.ORG>
Subject: Re: mmap and NFS

On Thu, 8 Aug 1996, J Wunsch wrote:
> As Fred Gilham wrote:
> > One of the users I support has written a program that uses mmap and
> > two communicating processes.  When he tries to mmap files on NFS
> > mounted partitions, [...]
> ``Stay away from mmap() on NFS!''  [John Dyson]

Yup, this is true. See the URL below for a pointer to a paper on how you
can make mmap'ed files for NFS work by modifying NFS in a few simple ways.
I had this working on 2.05R, but the changes are it seems too far-reaching
to get plugged into the freebsd tree (or the linux or netbsd tree for that
matter). Not lots of lines of code, but some lines of thought. Anyway, 
some of you might find it of interest. 

p.s. note that it's an FTP: not an HTTP:. :-(. Don't ask. 

Ron Minnich                |"If you leave out all the killings, D.C. has as       | low a crime rate as many cities" -- 
(609)-734-3120             |  D.C. Mayor Marion Barry 

------- End of Forwarded Message

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Jason R. Thorpe                             
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