Work

[Nick Krause]

On Fri, Jul 25, 2014 at 6:23 PM, Arlie Stephens <arlie at worldash.org> wrote:
> On Jul 25 2014, Nick Krause wrote:
>> > But if nothing like that is jumping out at you, maybe you should go look
>> > around and see if there's something in userspace that *does* jump out at you.
>>
>> I am interested in file systems and will be working on brtfs and ext4.
>> Cheers Nick
>
> If you want an annoying problem, explain and/or fix directory
> performance on ext4. I've got a server where an ls of a directory took
> 5 seconds, according to "time", even though it only has 295 entries at
> present.
>
> It's a rather large directory, 4 times the size of a normal directory
> in the opinion of ls -ld, and filefrag reports it has 7 extents.
>
> I'm also getting anecdotal reports of rename() taking unreasonable
> amounts of time, probably with at least one of the directories
> involved being in a similar state.  (They would have been created and
> populated by the same software.)
>
> Probably the directory had a large number of files and/or
> subdirectories some time in the past, and this is "expected
> behaviour".  Expected or not, it seems to me that it's about time that
> linux handles directories with something closer to the efficiency with
> which it handles files ;-)
>
> --
> Arlie
>
> (Arlie Stephens                                 arlie at worldash.org)


Sure Arlie,
I don't mind helping you out but you have to test this for me as this problem is
not happening on my hardware at least :).
Cheers Nick