386/ix freezes and crashes

Francois Pinard pinard at IRO.UMontreal.CA
Fri Aug 25 16:17:58 AEST 1989

Hello.  I would like to share some facts and eventually receive some
feedback about a few freezes and crashes I experienced with 386/ix
Unix 2.0.1.  Other people may have had similar adventures. Even then,
abstract these glitches, I would be quite satisfied with this system,
which is on several other aspects well behaved beyond my expectations.

1) The system freezes at various places while surface testing the
   disk.  In fact, character echo is being done, so the system is not
   really dead.  The very bad side effect of these is that alternate
   sector tables never get written, which further induce the system in
   unstable operations and prohibit the development of confidence.

2) The probability of a system crash increase drastically if I start
   several processes requiring a lot of memory each, to the extent it
   is worrying to launch big tasks without killing others first.

Those are the two main problems.  The following are, by comparison, of
subsidiary importance:

3) Getting out of cu may cause, sometimes, loss of a virtual terminal
   and of UUCP operations.  When cu starts, it establishes two tasks,
   ending cu will have one of these tasks to terminate, the other will
   hang unkillable, with a small, but non negligible probability.  An
   fsck will be mandatory at the next reboot.  This might be related
   to ~%nostop, but I've no evidence.

4) If there is any bad block in the free list of a file system, the
   system is not mountable.  If there is a bad block in the free list
   of the root partition, you've lost a system.  It would be nice if
   fsck was a least able, after having read a bad block, not to keep
   it part of its reconstructed free list.

5) A ttymap reset will hang the virtual terminal if done from a
   non-root user.  I'm not using nor even testing the reset option
Franc,ois Pinard                                    pinard at iro.umontreal.ca
(514) 588-4656           ``Vivement GNU!''          ...!uunet!iros1!pinard

More information about the Comp.unix.i386 mailing list