Re: stat benchmark

From: Carl Henrik Lunde
Date: Sun Apr 27 2008 - 20:14:09 EST


On Mon, Apr 28, 2008 at 1:29 AM, Soeren Sandmann <sandmann@xxxxxxxxxxx> wrote:
[...]
> For a directory of ~2360 files, chunks of a 1000 files is actually
> surprisingly worse than statting all of the files at once:
>
> Time to stat 1000 files: 1.008735 s
> Time to stat 1000 files: 0.738936 s
> Time to stat 366 files: 0.217002 s
>
> I guess this just shows that seeks really is pretty much all that
> matters. Glib should maybe use a larger chunk size.

I agree, if I remember correctly I did not find a directory on my local
disk where the best result was to sort a chunk instead of the complete
directory.

> I don't know if a general library outside glib would be useful. It
> seems that just telling people to "sort by inode before statting"
> would be just as effective as telling them "use this optimized
> library".

A library (like glib) could disable the feature for solid-state drives
and perhaps implement an alternative strategy for filesystems without
any inode/sector correlation.

So I think we should tell people to use glib. :-)

--
Carl Henrik
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