Xref: utzoo comp.arch:11346 comp.sys.mips:146
Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!apple!baum
From: baum@Apple.COM (Allen J. Baum)
Newsgroups: comp.arch,comp.sys.mips
Subject: Re: Memory utilization & inter-process contention
Message-ID: <34640@apple.Apple.COM>
Date: 11 Sep 89 17:59:22 GMT
References: <70663@yale-celray.yale.UUCP>
Reply-To: baum@apple.UUCP (Allen Baum)
Organization: Apple Computer, Inc.
Lines: 33

[]
>In article <70663@yale-celray.yale.UUCP> leichter@CS.YALE.EDU (Jerry Leichter) writes:
>I have never understood this need people have to use the VAX as the standard
>bad example of EVERYTHING.  In fact, the designers of the VAX worked in ways
>very similar to the way good RISC designers work today:  Hardware and software
>people cooperated, and there was an attempt to balance the complexity each
>had to deal with.
.....
>the compiler writers heavily influenced the design of the ISA, asking for
>things like 3-address arithmetic instructions in addition to 2-address and
>indexed addressing modes, but given the compiler technology of the day, this
>is what they thought would be useful to them.  Compiler technology has changed
>greatly since then, as has hardware technology.
>
>The main difference between the VAX design team and current design teams is
>probably in the inclusion of the OS designers.  The process structure of the
>VAX, the support in hardware for AST's, the security structure - all of these
>are direct reflections of the OS being developed.

Hear, hear! I'm not particularly a fan of VAX, but its getting a lot of bad
press from the RISC people because of its performance vs. the new chips.
This is NOT because it is a bad design, its because its an old design, and
the nature of the tradeoffs have changed. This includes not just compiler,
and OS technology, but lots of the hardware technology: memories, I/O, logic,
and packaging. These make a big difference on how a system is designed. 

The major fault of VAX proponents is that they haven't recognized that these
tradeoffs have made a difference, and they still think they can compete (on
the basis of performance, as opposed to just running old code).

--
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