Re: [PATCH storage v7 2/4] fix #7339: lvm: add discard action for removed volumes

[Fiona Ebner <f.ebner@proxmox.com>]

Am 30.06.26 um 2:15 PM schrieb Fiona Ebner:
> Am 16.06.26 um 12:13 PM schrieb Lukas Sichert:
>> On LVM storages backed by thin-provisioned SAN LUNs, removing an LV does
>> not release the allocated space on the backing storage. Using LVM's
>> `issue_discards` can avoid that, but makes `lvremove` issue the discards
>> while holding the cluster-wide storage lock, which can hit the lock
>> timeout for large volumes.
>>
>> Add an `on-volume-remove` property with an initial `discard` action. The
>> cleanup worker issues the discard for the renamed LV before the final
>> remove, so the long-running operation happens outside the storage lock.
>> When combined with `saferemove`, the worker zeroes and discards the LV
>> range by range, avoiding allocation of the whole LV with zeroes on
>> thin-provisioned backing storage.
> 
> If a storage has
> on-volume-remove discard=1
> saferemove 0
> then zero-out is still done. I would expect only discard to be done then.

My bad. As Lukas pointed out off-list, this is actually the case. It's
just done outside the $secure_delete_cmd helper.