[Ti] Kernal Panics

[Paul N. Reid]

On 05/06/2003 13:53, "Flanders, Camron Brent" <benhogan at ku.edu> wrote:

> I have a friend that has experienced a few kernal panics in the past
> week or so that have the words "corrupt stack" in the first line of the
> panic.  Anyone know what this is all about? and any ways to stop it, it
> happens almost once per day.
> 
> camron

Hey Camron, 

The 'Stack' and 'Heap' refer to the way the ram is utilized by the hardware,
and is similar to the they way most utilities 'optimize' your hard drives -
the information that rarely gets changed and contains the instruction sets
for how the machine is to work (the System, applications, and so on) is
stored on one "side" or "end" (for lack of a better word) of the disc. While
the other information that is often changed and represents all of the work
you have created (documents, graphics, and so on) is written to the opposite
"side" or "end" of the disk.  This way their is a gap between the two, such
that the changeable information has a lot of room to grow and change,
without threatening to overwrite the important information.

Often when their is a problem with the stack and heap, you never know it
because it doesn't tell you, but rather shows up as a symptom, like a finder
crash or system freeze up. You would merely get out of the symptom the
safest way possible, and restart the machine, thus purging the content of
the ram and reloading the stack and heap anew upon restart.

If you are getting the kernal panic during the start-up phase, then their
may be a problem with the ram chip itself, or possibly some major corruption
in the system software is being loaded from the HD to the RAM that gets
wonky before the system can finish loading. In this the case, then the first
thing I  would do would be to restart  the machine, Reset the Parameter RAM,
and let it start-up under single-user (option-'S') or verbose mode and
follow the syntax instructions provided there to run 'fsck'.  If that does
not change anything, I would next run a directory utility (the only that I
can recommend at this point would be DiskWarrior) to evaluate the directory,
verify and replace it if errors are found.

The next two steps should only be taken after the first two have been
unproductive, and are slightly more likely to be helpful if the kernal panic
happens only after the system has been completely loaded in  and you (or
your friend) have begun your work for the session.  Believe it or not, I
would suggest going to the hardware first if the machine in question has
more than one RAM chip, both or all of the chips are large enough to run OS
X on their own, you have the confidence, experience, and appropriate
antistatic safeguards and you have easy access to said chips (which may not
be the case if the machine is a PowerBook),  what you would do if all these
conditions are met, would be to pull al but one chip, and test them one at a
time - swapping chips - and try to determine if you can identify if you get
the Panic only when a particular RAM Module is used.

If even one of the above criteria are not met, or if you still have kernal
panics regardless of the chips being used, then back all of your  data up,
reformat the hard drive choosing the 'zero all data' option and reinstall OS
X and each of the applications *from their original CD's.  If the kernal
panics were only occurring when a particular app, open that app, create a
new document or project and beat the heck out of it.  If it was occurring
regardless of what you were working in do a little bit of everything. *DO
NOT*, however, attempt to move back or work on your real projects until you
are pretty sure the problem is gone.

After all of that, and especially if you were unable to test the RAM
yourself, It is probably time to take it someone with more training or
experience (if you trust them) or to a professional AASP Certified
technician.  You definitely want to exhaust all of your software options
before taking it to a professional - especially if it is under warranty

If any of this is unclear or you have any additional questions, please feel
free to contact me off-list if it feels more comfortable. otherwise, I will
keep my eyes open for additional posts/questions (hopefully with good news!)

ShrinkMan
------------------------------------------------------
Paul N. Reid, M.S.
AASP Certified Systems Technician
Point of No Return Productions
pnreid at cox.net

"Every cloud has a silver lining, except for the mushroom shaped ones, which
have a lining of iridium & strontium-90."