Messages in this thread | | | From | "Ulrich Windl" <> | Date | Wed, 24 Apr 1996 09:51:20 +0200 | Subject | Re: memtest86, built into kernel |
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On 23 Apr 96 at 17:09, Karl Keyte wrote:
> > > > > > Given that it happens so rarely, that parity is only 50% likely to > > > catch the error anyway, and that parity requires an extra 12.5% DRAM, > > > it doesn't seem worth it to me. ECC is more useful, since it will > > > correct single-bit errors rather than just hanging. > > > > > > -Matt > > No, surely the parity is virtually 100% certain to catch the error...?? > The only way it wouldn't is for more than the one bit to be in error > in such a way that the parity becomes valid again. If bit errors are > so rare, it's an unlikely situation, so the parity bits should be a > good test. However, it's so rare, and parity bits themselves can be > subject to error, I wouldn't bother with it. They don't either!
The probability that a reported parity error is due to a error in the parity bit is 1/9. Parity errors are rather rare; thus that type of error is even more unlikely.
> > Karl >
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