Re: [PATCH 1/2] fts: introduce the FTS_NOLEAF flag

[Pádraig Brady]

On 09/12/15 11:42, Kamil Dudka wrote:
> On Wednesday 09 December 2015 10:35:25 Pádraig Brady wrote:
>> On 09/12/15 06:34, Kamil Dudka wrote:
>>> The flag is needed to implement the -noleaf option of find.
>>> * lib/fts.c (link_count_optimize_ok): Implement the FTS_NOLEAF flag.
>>> * lib/fts_.h (FTS_NOLEAF): New macro, shifted conflicting constants.
>>
>> Is this exposed to fix issues with certain file systems,
>> or just in case there may be issues, or support easily
>> testing find without the leaf optimization?
> 
> All of the above I would say.  We can never verify that it works properly 
> for all white-listed file systems in all kernel versions (and all their 
> supported configurations).  There should always be a way for the user to 
> disable the optimization if needed, either for debugging, or to work around
> a file system bug.
> 
>> I see Jim said the current FTS implementation
>> would make -noleaf a no-op there:
>> https://lists.gnu.org/archive/html/bug-gnulib/2008-12/msg00280.html
> 
> Yes but it has never been reflected in find's documentation so the current 
> behavior hardly matches what users would expect.

On the other hand we've had no reports of issues with the
existing auto config done by FTS.  In my experience one
should jump through hoops to avoid config where possible.
Until we see a case where dirent.d_type is accurate while
noleaf is not appropriate, then I'm inclined to avoid the config.
If this was an issue then there would need to be associated
-noleaf patches to find(1), and also other FTS using tools.

I've applied the patch to ensure noleaf optimization is
enabled for NFS, and also applied my patch enabling it for XFS.

thanks,
Pádraig.