[Gluster-devel] Gluster Test Framwork tests failed on Gluster+Zfs(Zfs on linux)

[Anders Blomdell]

On 2014-09-04 13:08, Kaleb KEITHLEY wrote:
> On 09/04/2014 06:49 AM, Santosh Pradhan wrote:
>> Hi, Currently GlusterFS is tightly coupled with ext(2/3/4) and XFS.
>> Zfs (ZOL) and Btrfs are not supported at the moment, may get
>> supported in future (at least btrfs).
>> 
>> Thanks, Santosh
>> 
>> 
>> On 09/04/2014 03:34 PM, Justin Clift wrote:
>>> On 28/08/2014, at 9:30 AM, Kiran Patil wrote:
>>>> Hi Gluster Devs,
>>>> 
>>>> I ran the Gluster Test Framework on Gluster+zfs stack and found
>>>> issues.
>>>> 
>>>> I would like to know if I need to submit a bug at Redhat
>>>> Bugzilla since the stack has zfs, which is not supported by
>>>> Redhat or Fedora if I am not wrong?
>>> Definitely create an issue on the Red Hat Bugzilla, for the
>>> "GlusterFS" "product" ;> there:
>>> 
>>> https://bugzilla.redhat.com/enter_bug.cgi?product=GlusterFS
>>> 
>>> Since it's for the upstream Community, the official Red Hat
>>> "Supported" list isn't super relevant.
>>> 
> 
> There is no officially blessed file system for Community GlusterFS.
> The only requirement is that the file system support extended
> attributes.
And that it does not use 64-bit offsets, as can be seen in
http://supercolony.gluster.org/pipermail/gluster-devel/2014-July/041604.html
I've had bad experiences with replication and ext4 :-(

The design considerations in https://bugzilla.redhat.com/show_bug.cgi?id=838784
are to me quite dubious:

    However both these filesystmes (EXT4 more importantly) are "tolerant" in
    terms of the accuracy of the value presented back in seekdir(). i.e, a
    seekdir(val) actually seeks to the entry which has the "closest" true
    offset.
    
    This "two-prong" scheme exploits this behavior - which seems to be the
    best middle ground amongst various approaches and has all the advantages
    of the old approach:
    
    - Works against XFS and EXT4, the two most common filesystems out there.
      (which wasn't an "advantage" of the old approach as it is borken against
       EXT4)
    
    - Probably works against most of the others as well. The ones which would
      NOT work are those which return HUGE d_offs _and_ NOT tolerant to
      seekdir() to "closest" true offset.
    


> 
> As a guide to best practice, you may wish to look at what Red Hat
> officially supports for RHS GlusterFS — that is XFS. As you might
> expect, that gets the most testing and likely has the fewest bugs
> related to it. But people are successfully using other file systems,
> e.g. ffs on NetBSD and FreeBSD, HFS+ on Mac OS X, and btrfs and zfs
> on Linux.
> 
> You may certainly file bugs against Community GlusterFS with zfs. I
> will warn you though that due to various legal and political
> realities, probably (certainly) none of the Red Hat employees that
> work on GlusterFS will be able to devote time to it.
> 
> If you fix the bugs you find, please submit your fix in Gerrit. We
> will certainly accept fixes for legitimate bugs regardless of which
> file system you use. Our development workflow is described here
> http://www.gluster.org/community/documentation/index.php/Development_Work_Flow.
>
/Anders


-- 
Anders Blomdell                  Email: anders.blomdell at control.lth.se
Department of Automatic Control
Lund University                  Phone:    +46 46 222 4625
P.O. Box 118                     Fax:      +46 46 138118
SE-221 00 Lund, Sweden