Re: Memory testing program

Peter T. Breuer (ptb@dit.upm.es)
Sat, 14 Sep 1996 23:08:47 +0200 (MET DST)


>
> I have tried this program several times. It has not produced results
> that agree with other memory testers, and I don't trust it. I would

> Paul Matthews
> email: paul@matthews.com

But you can read the source code in memtest! All it does it write a
pattern at specified locations (increasing in linear order) and read it
back. If it is not what it wrote it logs an error. Fin. At the very
worst it's a conservative (i.e. it will miss some faults) test, but it
can't be wrong when it reports an error.

This is the write pattern code:
for (p = start; p < end; p++) {
*p = p1;
}
This is the read pattern code:
for (p = start; p < end; p++) {
if (*p != p1) {
error(p, p1, *p);
}

I don't see how you can claim that it is untrustworthy.
(it is my experience that the DOS memory testers are untrustworthy: run
them against each other on a known faulty machine and see what they say
:')

Sorry to prolong the thread. But memory errors ought to be eliminated
from the discussion of bugs, and advertising a memory tester as simple
as this is one way of doing it.

Peter T. Breuer
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