David Masover wrote:
Peter wrote:
On Fri, 01 Sep 2006 17:27:20 -0500, David Masover wrote:
snip...
both mkfs.reiserfs and fsck.reiserfs have -B option to accept list of
bad blocks. We thought that should be enough.
It really should. Why bother with a patch? Just write a wrapper
script
that runs badblocks and passes in the list to mkfs.
It was just a thought from userland. My perspective was that a user,
not a
hard-boiled geek, might get lulled into a false sense of security but
may
not have the wherewithal to write a wrapper. If nothing else, when the
final doc is written (did I say final?:)), it should include a notice
about not running badblocks.
Well, let's see... Most hard drives come more thoroughly tested at
the factory than anything badblocks would do. Also, it seems
redundant to have every single mkfs have to implement a badblocks flag..
I'd suggest a universal wrapper, then, or a modification to the "mkfs"
frontend, so that this works the same way across all filesystems.
Something like "mkfs -B -t reiser4"
I don't think that modern drives that fail writes are worth using for a
brand new file system.
While failing reads is quite common and can be caused by temporal issues
(dirt on the platter, a bad write, etc), failed writes are almost always
a sign that you have a serious issue. Almost all modern drives remap
each failed write to a bad sector automatically. This action only fails
if you have exhausted this remapping area (or have some really nasty
issue like a bad cable, bad write head, etc).
Having mkfs ignore bad writes would seem to encourage users to create a
new file system on a disk that is known to be bad & most likely not
going to function well. If a user ever has a golden opportunity to toss
a drive in the trash, it is when they notice mkfs fails ;-) This option
to mkfs sounds like an invitation to disaster.
The other tools (debugreiserfs, reiserfsck, etc) do need to be able to
handle bad blocks as well as possible since they are often needed during
a salvage operation. in order to recover data (which might need to be
migrated to a new disk). It is not clear to me that passing a list of
bad blocks helps them as much as a robust general purpose error recovery
support.
