Path: utzoo!news-server.csri.toronto.edu!rutgers!usc!jarthur!nntp-server.caltech.edu!pooh!madler
From: madler@pooh.caltech.edu (Mark Adler)
Newsgroups: comp.sys.next
Subject: Re: Non-parity SIMS
Message-ID: <1991Mar11.194924.11581@nntp-server.caltech.edu>
Date: 11 Mar 91 19:49:24 GMT
References: <23938@hydra.gatech.EDU> <1991Mar11.045612.1764@mp.cs.niu.edu> <1991Mar11.101750.1@capd.jhuapl.edu>
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Organization: California Institute of Technology, Pasadena
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Just to add to the misinformation about parity, I heard that the wait state
for parity is added only to write cycles, not read cycles.  This would make
sense (since the parity check on reads   can go on in parallel with using
the read data), and would further reduce the impact of the wait states, even
after taking into account cache hits.

Maybe Conrad can fill us in on the performance impact of parity.

Mark Adler
madler@pooh.caltech.edu