Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!ucsd!ucsdhub!hp-sdd!hplabs!hpda!hpcupt1!hpisoa1!vandys
From: vandys@hpisoa1.HP.COM (Andrew Valencia)
Newsgroups: comp.os.misc
Subject: Re: DG/UX -- Seybold's Review ( long )
Message-ID: <11590002@hpisoa1.HP.COM>
Date: 13 Sep 88 15:46:31 GMT
References: <602@spsd.SPSD.DG.COM>
Organization: Hewlett Packard, Cupertino
Lines: 18

/ hpisoa1:comp.os.misc / dds@spsd.SPSD.DG.COM (Dennis D. Sherod) /  7:02 pm  Sep 11, 1988 /

>DG needs to distinguish its approach to Virtual Memory Management from
>those used by both Hewlett-Packard and IBM.  Both HP/UX and AIX allow
>for users to have transparent access to programs that do not fit into
>physical memory by swapping segments in and out of main memory.  DG's
>approach allows users to have transparent access to programs that do
>not fit into physical memory by demand paging on a per page basis.  DG
>needs to be clear on how its approach is superior to this alternative.

    Could you explain this statement?  Our VM system is essentially the
BSD 4.2 VM system, with some modifications for performance and real-time
latency.  Like 4.2, our system can swap out user processes.  But it is also
perfectly capable of doing virtual paging.  Doing only demand-paging
might be a win, but I'd be interested to hear in exactly what ways it
manifests itself for DG over a system like 4.2/4.3.

					Andy Valencia