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To: Kevin Martin <sigma@pair.com>
cc: freebsd-bugs@freebsd.org
Subject: Re: Randomly modified executables... 
In-reply-to: Your message of "Fri, 07 Jun 1996 14:48:47 EDT."
             <199606071848.OAA09748@pair> 
Date: Fri, 07 Jun 1996 16:44:23 -0700
Message-ID: <17108.834191063@time.cdrom.com>
From: "Jordan K. Hubbard" <jkh@time.cdrom.com>
Sender: owner-bugs@freebsd.org
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> system and continue.  In one case, cksum reported a file as different, but
> it was OK immediately afterwards.  Most of the changes have occurred under
> extremely light load, in some cases with only one user logged in.  There is
> no evidence of foul play.

I've seen this kind of behavior too.  Except for one instance when it
was actually a VM system bug (and this was a LONG time ago), it turned
out to be bad cache ram in every instance.  Single bit errors in the
cache were causing files to show up with erroneous contents.  If you
do a `make world' in a continuous loop, you'll find that it aborts
occasionally with a syntax error in one of the source files.  Go look
at the file in question and you'll find some strange error where a
character has changed its value in some strategic spot.  This is a
sure sign!

					Jordan