Don's changes to fsck on 4.x ...

[Don Lewis]

On  7 Nov, Marc G. Fournier wrote:
> On Sat, 6 Nov 2004, Don Lewis wrote:
> 
>> On  6 Nov, Marc G. Fournier wrote:
>>>
>>> Well, finally had a reason to use it, and its running right now ... seems
>>> a bit slower in phase 2 then before ... is to be expected?  Looking
>>> through the patch, it seems that all pass's were affected, so this might
>>> be now the norm ... after ~39minutes running on a very large file system,
>>> hitting ctl-T periodically, I'm up to about 50% through Phase 2 ... so far
>>> *knock on wood* no errors being generated by fsck itself, but that doesn't
>>> mean anything :)
>>
>> Under normal circumstances, there shouldn't be any noticeable difference
>> in performance.  If there are a lot of zero link count files, phase 1
>> should be very slightly faster because the zero link count file list no
>> longer needs to be allocated, and phase 4 should be a lot faster. Most
>> of the time in phases 1 and 2 is consumed by disk reads.  The only
>> change to phase 2 was the addition of the new inode states to a couple
>> of case statements and an if statement which should not affect the
>> amount of I/O done and CPU time would only be affected by a miniscule
>> amount, so I would not expect any change to the performance of that
>> phase.
> 
> Hindsight is 20/20, but I should have trap' the output ... I saw several 
> 'ZERO LENGTH DIRECTORY' messages in Phase 4 still ... should I have seen 
> any at all?

Yes.  The behaviour should be exactly the same as before.  The only
difference is that phase 4 should run a lot faster if there are a lot of
UNREF files and directories.