Re: 2 question about XFS fragmentation and _fsr

Stan Hoeppner
2011-04-11T20:33:56Z

Janos Haar put forth on 4/11/2011 12:39 PM:

> In the result, actually we have >6TB images on the 3TB disk, wich is
> 97.9% fragmented.

How much free space does the filesystem have? How big is each image
file? For xfs_fsr to work properly it must have sufficient free space
in the filesystem.

> Basically the sparse RAW disk images should be more faster accessible
> than the original drive, because this is 4disk raid, instead of one, AND
> the head don't need to travel through the empty space of the drive...

It sounds like you may have some other issues besides filesystem
fragmentation.

> The XFS_FSR can be good for me or not?

If you have plenty of free space.

> Question 2:
> One of our customers have one storage wich is exactly the same like the
> one wich is described on the Q1, but only used for samba storage for
> storing media files (big files.)

Writing large files sequentially shouldn't cause fragmentation.

> I am sure, there is no torrent or similar, and i have told to the
> customers on the beginning "don't write more files parallel, to avoid
> fragmentation", but today the storage is >95% fragmented.
> The customer sad, he only does file write one by one, and nothing more.
> How can this be?

What were the mkfs.xfs arguments you used when creating these
filesystem? Please share xfs_info output for the filesystems in
question, and details of the underlying hardware RAID storage.

--
Stan