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From: karsh@trifolium.esd.sgi.com (Bruce Karsh)
Newsgroups: comp.arch
Subject: Re: Workstation Data Integrity
Message-ID: <68505@sgi.sgi.com>
Date: 4 Sep 90 22:39:29 GMT
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In article <1990Sep4.163619.24726@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:

>A hard failure is usually preferable to a silently wrong answer.

Given that a memory system is otherwise properly designed and tested
and uses modern 4Mbit DRAM memory chips, is there any evidence that
memory parity makes a measurable difference in the silent wrong answer
rate?

The memory failure component of the silent wrong answer rate seems to be so
small as to be insignificant.

If the answer is no, then isn't parity just a historical and cutural
artifact from the days when parity really was necessary?

			Bruce Karsh
			karsh@sgi.com