dynamic inode allocation

[Mag Gam]

On Mon, Sep 1, 2008 at 4:39 PM, Theodore Tso <tytso at mit.edu> wrote:
> On Mon, Sep 01, 2008 at 04:29:06PM -0400, Mag Gam wrote:
>>
>> So, if a reiserFs filesystem is damaged and it naturally do a fsck.
>> The fsck basically recreated the b-tree by scanning from 1 to end of
>> the filesystem?
>
> If the filesystem is sufficiently damaged such that portions of the
> b-tree can't be found, then yes.  Otherwise, the data would be totally
> lost.  As you can imagine, scaning every single block on the disk to
> see if it looks like filesystem metadata is quite slow, so naturally
> the reiserfs's fsck will avoid doing it if at all possible.  But if
> the root or top-level nodes of the B-tree is damaged, it doesn't have
> much choice.
>
>                                                - Ted
>
>

But, if thats the last and worst case scenario why don't they do the
full scan? Sure its going to take a long time if its a big filesystem
(there should be no changes since it would be unmounted), but its
better than not having any data at all...