[pve-devel] [PATCH pve-manager] Add "SSD" property to IDE, SATA, and SCSI hard drives

[Wolfgang Bumiller]

On Wed, Nov 07, 2018 at 12:20:37PM -0500, Nick Chevsky wrote:
> I think there may be some confusion here that the "SSD" flag should only be
> used with storage that is actually backed by physical SSDs, and that's not
> the case: Just like you can emulate hardware in a guest that you don't
> actually have in the host, you may want to emulate SSDs in a guest even if
> the storage is backed by rotational HDDs. Benefits of this include:

The idea is not to enforce it by storage, but to have the storage
define the default for when nothing is configured in the guest config.
(The issue with that, however, is live migration as well as
live-snapshots after live-moving the disk to another storage).

The argument would actually be stronger for the `discard` option, as eg.
I'd very much like `discard` to be on-by-default on lvm-thin or zfs.
Then again, for `discard` it would probably be enough if the GUI decided
on default checkbox values in the creation wizards based on storage type
(this wouldn't have the migration issue)...