Suggested. File system

[jphipps]

I was going to test out using either XFS or BTRFS on a few drives.  From your testing, is there a better file system to use?

[limetech]

I was going to test out using either XFS or BTRFS on a few drives.  From your testing, is there a better file system to use?

Why not try both?  Btrfs is a lot faster in formatting a large hdd.  But xfs is a lot more mature.

 

For normal NAS use (accessing files via network) there is not much difference between any of the file systems since network tends to be the speed bottleneck.

[SSD]

If I remember right, one of the advantages of BTRFS is that if you have duplicate information (files that are very similar like Docker containers), that BTRFS has an ability to reuse portions and use less space? So if you have a disk containing VMs or Backups, that a BTRFS would be more efficient?

 

But I've also read the BTRFS has issues knowing exactly how much space is used vs free. So if your goal is to fill a disk to the brim, it may not be a great choice.

[JonathanM]

So BTRFS has native deduplication? One of my heavy use cases for unraid is a repository for drive recovery efforts, 99.99% windows system drives with the user files. If I read this correctly, all the 1000's of files in system32 etc that are duplicated for each recovery would automatically not take up extra space? If that's so, my data storage total requirement just got WAY smaller.

[jphipps]

I am migrating data off 3 drives, so I will try out both and see how they do.. 

 

Thanks

[jonp]

So BTRFS has native deduplication? One of my heavy use cases for unraid is a repository for drive recovery efforts, 99.99% windows system drives with the user files. If I read this correctly, all the 1000's of files in system32 etc that are duplicated for each recovery would automatically not take up extra space? If that's so, my data storage total requirement just got WAY smaller.

No it does not have native deduplication.  It does support snapshotting and copy on write.

[limetech]

There is some support, never tried it though:

https://btrfs.wiki.kernel.org/index.php/Deduplication

 

btrfs does support compression:

https://btrfs.wiki.kernel.org/index.php/Compression

 

You'll be able to add this mount option in a future release.

 

 

[BRiT]

How do the new filesystems compare with ReiserFS under the following conditions:

 

Recovering from an accidental delete?

Recovering from filesystem corruption?

 

[jphipps]

Setup a few disks as BTRFS and one as XFS and ran some dd speed test to see how it compared.  This is an older machine with slower 2TB drives and running a 5GB file transfer from /dev/zero to the /mnt/diskX:

 

Reiserfs  approx: 61MB/s

XFS approx: 61MB/s

BTRFS approx: 62MB/s

 

I didn't reformat any of the same disks , I use different disks for each test.  Guess the performance is not much different between the various filesystems.  And it was pretty consistant over several runs.

 

[garycase]

Not surprising.  The speed of disk transfers is driven almost exclusively by the sustained data rate of the drives.    File systems have very little to do with it.    Other operations (e.g. formatting) can be different, depending on the structure the file system requires on the drive ... but the speed of data transfer is a function of how fast the disk can provide it.

 

[WeeboTech]

File systems have very little to do with it.

 

This is not entirely true. writing to a journaled filesystem has a penalty in itself.

Couple that with parity operations and it becomes part of the potential speed limit.

 

During my tests with recent drives, writes (scribbles) to a non filesystem drive directly to the drive with DD were faster then filesystem writes. Not by allot, but it was measurable.

 

The same went for reads. Reads from a newly formatted filesystem with a very large file were slightly slower then a direct dd from the drive.

 

60MB/s to a 2TB parity protected drive is pretty respectable.

If it were to a drive outside of parity operations, that should be closer to 100MB/s on the outer tracks.

 

on my test system with recent drives (when I had it).

3TB 7200 RPM drives wrote and read directly at 190MB/s

4TB 5400 RPM drives write and read directly at 160MB/s

[dalben]

Out of the three file systems on offer, which would be the most suitable for the Parity disk ?

[BRiT]

Out of the three file systems on offer, which would be the most suitable for the Parity disk ?

 

The parity disk does not use a filesystem.

[dalben]

Out of the three file systems on offer, which would be the most suitable for the Parity disk ?

 

The parity disk does not use a filesystem.

 

Well that settles that then.  Thanks.

[BRiT]

Additional questions related to filesystems and how they compare (ReiserFS, XFS, BTRFS):

 

Is there a way of reading the filesystem from a Windows OS?

[garycase]

Additional questions related to filesystems and how they compare (ReiserFS, XFS, BTRFS):

 

Is there a way of reading the filesystem from a Windows OS?

 

Do you mean reading the disks, if they're attached to a Windows machine?  If so, then Yes for Reiser and XFS, but not directly for BTRFS ...

 

For Reiser:  http://www.diskinternals.com/linux-reader/

 

For XFS:  http://archive.siejak.pl/fsproxy/wikka8979.html?wakka=HomePage&show_comments=1  (can also read Reiser)

 

For BTRFS:  You could take a hint from fsproxy, and simply create a Linux VM on your Windows machine, load it with a Linux distro that supports BTRFS, and attach the drives to the VM.    Then just create a network share to the host, and you can then read the BTRFS partition in the VM, and access the data in Windows.

 

 

If you mean is there a way to tell from Windows which file system the disks on your UnRAID server are using, that's easy => just click on the disk on the main page of the Web GUI and one of the pieces of information it shows is the file system type.

 

[dtempleton]

Additional questions related to filesystems and how they compare (ReiserFS, XFS, BTRFS):

 

Is there a way of reading the filesystem from a Windows OS?

 

Brit's asking the question that has kept me from fully embracing unRAID:  As it stands now if my motherboard goes tits-up I have no access to the data stored on my reiserfs-formatted drives. Very sad.  What I'd like is to be able to remove the drives and mount them on my media computer (for me a Mac) and be back in business.

 

The semi-moribund but functional MacFUSE project (or its apparent successor OSXFUSE http://osxfuse.github.io/ ) can apparently enable access to filesystems popular on Linux and other platforms. 

 

My question is which of the two 'new' FS for unRAID is better for at least reading with MacOS/ OSXFUSE?  I'm testing xfs right now but would be happier hearing from someone who had direct experience.

 

Thanks,  Dennis

 

EDIT:  This fuse-xfs driver http://sourceforge.net/projects/fusexfs/ for OSX-FUSE apparently offers read-only access, a bit slow, to xfs volumes on OSX. /EDIT

[Donovan]

Edit: We all posted a reply in a fairly short period of time 

 

Found this via Google, 32-bit only. ReiserFS and XFS:

http://www.crossmeta.org/crossmeta.html

 

ReiserFS:

http://yareg.akucom.de/

http://www.diskinternals.com/linux-reader/

probably others.

 

I wouldn't use any of these tools except in a recovery situation, personally.