Yes, zvol like feature where a btrfs subvolume like construct can be made available as a LUN/block device. This device can then be used by any application that wants a raw block device. iscsi is another obvious usecase. Having thin provisioning support would make it pretty awesome.
Suman On Mon, Feb 25, 2013 at 5:46 PM, Fajar A. Nugraha <l...@fajar.net> wrote: > On Tue, Feb 26, 2013 at 11:59 AM, Mike Fleetwood > <mike.fleetw...@googlemail.com> wrote: >> On 25 February 2013 23:35, Suman C <schakr...@gmail.com> wrote: >>> Hi, >>> >>> I think it would be great if there is a lvm volume or zfs zvol type >>> support in btrfs. > > >> Btrfs already has capabilities to add and remove block devices on the >> fly. Data can be stripped or mirrored or both. Raid 5/6 is in >> testing at the moment. >> https://btrfs.wiki.kernel.org/index.php/Using_Btrfs_with_Multiple_Devices >> https://btrfs.wiki.kernel.org/index.php/UseCases#RAID >> >> Which specific features do you think btrfs is lacking? > > > I think he's talking about zvol-like feature. > > In zfs, instead of creating a > filesystem-that-is-accessible-as-a-directory, you can create a zvol > which behaves just like any other standard block device (e.g. you can > use it as swap, or create ext4 filesystem on top of it). But it would > also have most of the benefits that a normal zfs filesystem has, like: > - thin provisioning (sparse allocation, snapshot & clone) > - compression > - integrity check (via checksum) > > Typical use cases would be: > - swap in a pure-zfs system > - virtualization (xen, kvm, etc) > - NAS which exports the block device using iscsi/AoE > > AFAIK no such feature exist in btrfs yet. > > -- > Fajar -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
