Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!uunet!virtech!cpcahil
From: cpcahil@virtech.uucp (Conor P. Cahill)
Newsgroups: comp.unix.i386
Subject: Re: adding bad blocks using 386/ix
Message-ID: <1990Mar6.141232.668@virtech.uucp>
Date: 6 Mar 90 14:12:32 GMT
References: <511211@nstar.UUCP> <PCG.90Mar3215337@odin.cs.aber.ac.uk> <PCG.90Mar3215633@odin.cs.aber.ac.uk> <39560@ism780c.isc.com>
Reply-To: cpcahil@virtech.UUCP (Conor P. Cahill)
Organization: Virtual Technologies Inc., Sterling VA
Lines: 22

In article <39560@ism780c.isc.com> darryl@ism780c.UUCP (Darryl Richman) writes:
>This is a better approach than automatically remapping because that
>prevents the user from attempting to reread the bad sector and possibly
>retrieving the data.

PLEASE do not add automatic remapping of bad blocks to 386/ix.  Once upon a
time I happened to be using Bell Technologies System V Rel 3.2 (which had
automatic re-mapping) and a static charge caused the disk controller to 
report a bad read for any blocks that were currently in process of
being read/written.  This wrecked havoc on the file system when portions
of the root, etc, and usr directories were automatically remapped.
Even portions of several executables were hit.

This is a real pain in the a**.  The capability to add entries to the
bad block table while running is a good capability, but PLEASE DO NOT
MAKE IT AN AUTOMATIC PART OF THE DISK DRIVER.


-- 
Conor P. Cahill            (703)430-9247        Virtual Technologies, Inc.,
uunet!virtech!cpcahil                           46030 Manekin Plaza, Suite 160
                                                Sterling, VA 22170