On Fri, 07 Sep 2012 09:35:10 +0300, Itamar Heim <ih...@redhat.com> wrote:
> On 09/07/2012 08:21 AM, M. Mohan Kumar wrote:
> > On Thu, 6 Sep 2012 18:59:19 -0400 (EDT), Ayal Baron <aba...@redhat.com>
> > wrote:
> > For start using the LVs we will always do truncate for the required
> > size, it will resize the LV. I didn't get what you are mentioning about
> > thin-provisioning, but I have a dumb code using dm-thin targets showing
> > BD xlators can be extended to use dm-thin targets for thin-provisioning.
> so even though this is block storage, it will be extended as needed? how
> does that work exactly?
> say i have a VM with a 100GB disk.
> thin provisioning means we only allocated 1GB to it, then as the guest
> uses that storage, we allocate more as needed (lvextend, pause guest,
> lvrefresh, resume guest)
When we use device=lv, it means we use only thick provisioned logical
volumes. If this logical volume runs out of space in the guest, one can
resize it from the client by using truncate (results in lvresize at the
server side) and run filesystem tools at guest to get added space.
But with device=thin type, all LVs are thinly provisioned and allocating
space to them is taken care by device-mapper thin target
automatically. The thin-pool should have enough space to accomoodate the
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