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Date: Sun, 26 Oct 1997 19:18:24 -0800 (PST)
From: Tom <tom@sdf.com>
To: Alfred Perlstein <perlsta@cs.sunyit.edu>
cc: hackers@freebsd.org
Subject: Re: Parity Ram
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On Sun, 26 Oct 1997, Alfred Perlstein wrote:

> > > more bits means more chance of error even if they are "error-correcting"
> > > bits?
> > 
> >   And how is that bad?  Even simple parity systems will catch 100% of all
> > single bit errors, regardless of where the bit appears.
> > 
> >   More bits mean more redundancy.  That means it gets safer, not riskier.
> 
> ok, 9 to 8 is a 1.125 difference in the ratio?
> i think, what he means is that with a large amount of memory you just have
> more bits that can go bad...

  All the more reason to use parity.

> i'm not really sure though, just playing devil's advocate...
> 
> you still have the same amount of protection, just more risk.

  The same goes for everything.  If the MTBF of one item is X, the MTBF of
N such items is X/N.

Tom