[zfs] BSD ZFS vs. illumos ZFS

[Justin T. Gibbs]

On Oct 9, 2013, at 11:34 AM, Tim Cook <tim at cook.ms> wrote:

> 
> 
> On Wed, Oct 9, 2013 at 12:09 PM, Matthew Ahrens <mahrens at delphix.com> wrote:
> 
> 
> 
> On Wed, Oct 9, 2013 at 9:49 AM, Pawel Jakub Dawidek <pjd at freebsd.org> wrote:
> On Wed, Oct 09, 2013 at 06:36:02PM +0200, Radio młodych bandytów wrote:
> >
> > Openzfs has a nice feature comparison:
> > http://open-zfs.org/wiki/Features
> 
> It clearly wasn't done by a FreeBSD person:)
> 
> The features available only in FreeBSD:
> - TRIM support (actually also in ZoL, AFAIK).
> - Ability to boot from any ZFS pool (other platforms are limited to one
>   top-level vdev which can be either disk or a mirror (I hope that's
>   correct)).
> - Quick listing when using options '-o name -s name' - it is at least
>   100 times faster than alternatives. Very handy when there is huge
>   number of snapshots.
> - ZFS-super-owner - allows regular users to perform file system
>   operations as root. This is possible when the file system was mounted
>   by the user, the user is owner of this file system (we force nosuid
>   option then). Used in FreeBSD netperf cluster, so regular users can
>   installworld (which set proper ownership of files) to their netbooted
>   datasets from a build machine.
> 
> I'm sure I'm missing some.
> 
> PS. Yes, I know I should just put it onto wiki, but if anyone has some
>     spare cycles I'd be grateful for doing it.
> 
> 
> I added it to the Talk page (http://www.open-zfs.org/wiki/Talk:Features).  Would be great if someone from the FreeBSD community could take the time to verify, format and document these on the Features page.
> 
> --matt
> 
> 
> From a downside perspective I beleive FreeBSD still has no solid block target stack.

A new, in kernel, iSCSI target and initiator stack (funded by the FreeBSD Foundation) is available in FreeBSD/head and will be included in FreeBSD 10.  It makes use of the FreeBSD CAM Target Layer (CTL) stack (sponsored by Copan/SGI and SpectraLogic) which is similar to COMSTAR.

> I believe SpectraLogic gave some code to the effort but it's not yet fully baked?

The code from Spectra makes block serving more efficient.  It is fully baked, but not yet upstreamed.

>  There's also no ALUA support that I'm aware of - GEOM only supports active/passive pathing.
> 
> From the NAS side of things, FreeBSD has no concept of an in-kernel licensed CIFS stack, it relies on SAMBA.

Spectra relies on the Likewise stack.  If there are others interested in running this on FreeBSD, please contact me.  We've been planning for some time to push our version of Likewise out on GitHub or something similar to get more collaboration on improving it.  Although not in kernel, it does have very good performance.

>  The one thing I would say on this front is it's likely to be less of a concern as SAMBA embraces SMB3.  I don't see any way that the in-kernel stack in illumos is getting smb3 support unless there's work and money behind it I'm not aware of.

So long as Samba remains GPLv3, there will be interest in developing an alternative.

--
Justin