bug in ufs?

[Kostik Belousov]

On Tue, Jul 07, 2009 at 12:15:46AM +0400, Marat N.Afanasyev wrote:
> Kostik Belousov wrote:
> >On Mon, Jul 06, 2009 at 09:45:45PM +0400, Marat N.Afanasyev wrote:
> >>i have a huge amount of small files on the source systems, as you can 
> >>see they have about 20 million files and almost each of them is jpeg or 
> >>gif. afaik, there are no sparse files at all.
> >>
> >>i still cannot figure out what is it: a free space leak in ufs2+su or 
> >>bug in statfs(3), that is used in df, or something else.
> >
> >My guess that it is due to fragmentation.
> >As an experiment, try to create 1-byte file. Does it work on the filesystem
> >in described state ?
> 
> I can create small files, as many as i have patience, maximum size of 
> such "small file" is 14336, so. it seems that if file is no greater than 
> (block_size-2048) it can be created. larger file cannot be created.
> 
> imho, fragmentation on filesystem should be very low, there were no 
> deletions on it, just creations.

The fragmentation on UFS usually means using fragments for the file tails,
not having file sequential blocks allocated in the non-sequential disk
blocks.

You experiment confirms my hypothesis.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 195 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-stable/attachments/20090706/5d9fac15/attachment.pgp