Re: storage API and ZFS

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, Oct 18, 2007 at 06:58:38PM +0100, John Levon wrote:
> 
> Accidentally deleted your reply Richard, sorry.
> 
> ZFS 'pools' are aggregates composed of some number of real devices. LVM
> confuses me so I don't know what they map on to, but the basic idea is
> that you can carve filesystems out of such pools at will.

That is the same concept as an LVM volume group.

> You can also carve out 'volumes' - these appear as a disk device in
> /dev/zvol/dsk/poolname/volumename

That is the same concept as an LVM logical volume

> It's the latter that you use in Xen to hold domU root filesystems (or
> you can use a normal file on whatever file system, or a real device, as
> desired).
> 
> What might be tricky is anything that claims to return "space left",
> depending exactly on what you want it to mean. But (I think) certain LVM
> setups have similar issues.

Asking 'space left' for a volume directly isn't really applicable - that's a
property of the file system on the volume instead.  'Space left' in a pool
is basically an indication of how much space is available for allocating
additional pools. Allowing you ask 'is that space to allocate a 10 GB
volume in this pool?' rather than just blindly trying & failing

Dan.
-- 
|=- Red Hat, Engineering, Emerging Technologies, Boston.  +1 978 392 2496 -=|
|=-           Perl modules: http://search.cpan.org/~danberr/              -=|
|=-               Projects: http://freshmeat.net/~danielpb/               -=|
|=-  GnuPG: 7D3B9505   F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505  -=| 

--
Libvir-list mailing list
Libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list

[Index of Archives]     [Virt Tools]     [Libvirt Users]     [Lib OS Info]     [Fedora Users]     [Fedora Desktop]     [Fedora SELinux]     [Big List of Linux Books]     [Yosemite News]     [KDE Users]     [Fedora Tools]