Laptop Saved! (was RAM Mapping Script)

[Jim Kuzdrall]

   Since the commenters made a very good case that bad RAM byte 64h 
should not affect Linux, I retested the RAM a 35C (maximum operating 
temperature for the Dell Inspiron 2650 laptop) to see if the rest of 
the RAM had weak bytes.  Only 64h tested bad.

   Since the chamber was going, I removed the hard drive to retest it at 
the higher temperature.  Rather than just a basic e2fsck test (which 
had been done several times), I added the -c option (badblocks).  Oh 
Oh.  The drive hung up about 20 minutes through the test with its 
"access light" on steady but giving no response.

   The drive tested the same at 20C with either the -c or -c -c options.  
However, it always passed e2fsck OK without the -c option set.  Another 
similar drive passed all of these tests OK, so the setup is valid.

Bad drive: Hitachi Travelstar 2.5" 40GB 5400rpm Feb-03

Passed: e2fsck -f -n -t -v /dev/sdb2
Failed: e2fsck -c -c -f -n -t -v /dev/sdb2
Failed: e2fsck -c -f -n -t -v /dev/sdb2
Passed: badblocks -b 4096 -v /dev/sdb2 9504871 (read only)
Failed: badblocks -b 4096 -n -v /dev/sdb2 9504871 (non-destructive r/w)
Passed: e2fsck -f -n -t -v /dev/sdb2 (no bad blocks although badblocks 
just failed)

    So it appeared to be a hangup in the drive's internal controller 
when it has a long series of read/writes to do.  The "locate" database 
search may have triggered it in situ.  I doubt I will ever know and no 
longer care.

Cost of saving Dell Inspiron 2650 (original cost ~$800)
"Technician" @ $40/hr 57 hr ......      $2280.00
Book "Understanding the Linux Kernel"      49.95
Ice cream to sooth nerves (6 times)        33.37
Replacement hard drive (160GB)             93.75
Rebate from wife for saving environment   -22.78
                                 Total   2434.29

Jim Kuzdrall