Path: utzoo!utgpu!watserv1!watmath!att!pacbell.com!ucsd!swrinde!elroy.jpl.nasa.gov!decwrl!world!ksr!jcw
From: jcw@ksr.com (Jay Wilkinson)
Newsgroups: comp.os.aos
Subject: Re: DG/UX on an MV/20000???
Message-ID: <1902@ksr.com>
Date: 25 Jan 91 19:48:57 GMT
References: <28117.279dbffe@kuhub.cc.ukans.edu>
Sender: news@ksr.com
Lines: 25

brownrigg@kuhub.cc.ukans.edu writes:

>(this isn't exactly the right news group, but its as close as they come...)

>Can anybody share their experiences with DG/UX running under the MV
>architecture?  It was indicated by the local people that Unix and the MVs
>were a very poor match, and that performance was atrociously slow.  I hope
>this isn't true!  What would be peculair about the MV arch. that would
>promote this?

FYI:  The biggest pain with UNIX and MV arch that I was aware of was that
word pointers were not byte addresses.  This caused endless problems with
many applications that assumed that all pointers were byte pointers.  DG
eventually added a switch to allow C to force all pointers to byte addresses
as they were stored to memory. ugh!
	I also remember NULL pointers causing problems, any read/write to 0
caused a protection fault which would normally cause program termination.

	-- Jay "ex-MV-guru" Wilkinson   jcw@ksr.com

--
Jay C. Wilkinson                         jcw@ksr.com
Kendall Square Research Corp.            uunet!ksr!jcw
170 Tracer Lane                          Telephone:  (617) 895-9403
Waltham, MA  02154-1379                  FAX: (617) 890-0996