From: jefftep@cs.utexas.edu (Jeffrey Grills)
Newsgroups: comp.os.linux
Subject: Maxtor 7213a update
Date: 9 Oct 1992 04:20:31 -0500
Organization: CS Dept, University of Texas at Austin
NNTP-Posting-Host: ozona.cs.utexas.edu


I've spent the last several days playing with componets, trying to
track down the causes of my linux problems.  It seems it may have to
do with my maxtor 7213a harddrive.  I've read everything through this
newsgroup on this drive in a long time, but I thought I would tell you
the results of some of my testings... Maybe you'll see something I've
overlooked.

I have a friend with a AMD 386/40 with an IDE drive, and he was nice
enough to lend it to me, and even allowed me to repartition his harddrive.
Good friend, eh?  Anyways, by swapping pieces, I've had the following
successes and failures:

My system:
  linux 0.98 pl1
  inter 386 33
  maxtor 7213a PCBA 63p1
  minix fs
  5mb ram
  7mb swap


His:
  linux 0.98pl1
  amd 386 40
  kalok 115mb hd
  minix fs
  4mb ram
  9mb swap

His Kalok drive gave me the nefarious Unexpected Interrupt messages,
but otherwise worked fine.  I dumped a copy of my linux fs to his drive
to test.  My testing consisted of compiling the kernel.  On his system,
it worked fine.  On mine, gcc dies either because of a signal 11 or a
text file looks corrupted (but isn't when I verify it).

With his HD in my system, it worked.
With my HD in his system, it failed.
With 8mb ram in my system, my hd, and no swap, it worked.
With both hd's in my system, mine used as root, his as swap, it failed.
With either his or my 4mb, and my hd, it failed.
With either his or my 4mb, and his hd, it worked.

This is interesting to me.  When gcc didn't need to swap (because I had
8mb ram), it worked.  So I thought, maybe, linux just couldn't swap to
a maxtor.  But when I used my drive as root, and his swap partition,
it still failed.  Quite intriguing.  I can't quite figure out why this
would be.  Though, the fact that simply swapping the ram didn't make
a difference implies it's not a ram-quality problem, or I'd expect to
see that with all 8mb.  (shrug)  This baffles me.

Whenever the kernel would compile, it would do so cleanly, and well, 
on one attempt, and the next attempt too.  Whenever it wouldn't compile,
it took many attempts to get it to compile to completion.  So, this
problem creeps up regularly in making the kernel.

I will call maxtor tommorrow and ask about this.  I also intend on
getting the new disks on TSX and reinstalling gcc, and seeing if
(for some twisted reason) that fixes things.

I have never had any error messages abotu the HD dumped to my screen
by the linux kernel.  No HD timeouts, resetes, unexpected interrupts,
nothing.

Finally, is there any way that buffer validation can be done in the
kernel, so we can tell if buffers/cache/whatever gets munged somehow?


If it were not for this little problem, I'd be such a happy camper.
As it is, I'm going bald at the age of 21... (sigh)

please forward all questions you may have to me, either here or in
mail.  if you have a maxtor 7213a, please tell me your tale...


Merry Linux,

-- 
-------------------------+--------------------------------------------------
jeff grills              | "Sometimes i see myself so clearly, because I
jefftep@cs.utexas.edu    |   see nothing at all.  This feeling of emptiness
Undergrad Lab, UT Austin |   flees my soul, leaving even less behind."  -me