[pve-devel] [Enhancement request] Thin Provisionning problems.. need to zero LVM disks before deleting a VM

[Floris Bos / Maxnet]

On 03/07/2012 11:05 AM, Dietmar Maurer wrote:
>> Datacore suggests us to zero disks before doing lvremove to tell the SAN the
>> space is really available in order to allow San Melody to reclaim the unused
>> space.
> Just found this: http://osdir.com/ml/linux-lvm/2011-02/msg00011.html
>
> The idea is to use TRIM??

I do not know if it's available in the LVM version shipped with Debian, 
but in Centos 6 there is indeed the "issue_discards" setting you can set 
in lvm.conf to issue trim commands to the drive when lvremove and 
lvreduce is used.

> Just committed a fix:
>
> https://git.proxmox.com/?p=pve-storage.git;a=commit;h=88c3abaf6e7c1ce320e69e5753cffcc2c12264e2
>
> we do this for all LVs. Let's see if user complains.

Complaining user here.
I don't like the concept of extra writes being sent to my SSD. Not sure 
if it detects zero writes automatically.

-- 
Yours sincerely,

Floris Bos