On Wed, May 02, 2018 at 15:39:07 -0400, John Ferlan wrote:
On 04/25/2018 11:15 AM, Peter Krempa wrote:
Enabling discard for the storage node allows the format drivers to discard snapshots and other things, while configuration of the format layer actually decides whether to actually discard data on request from the host.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> --- src/qemu/qemu_block.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
Isn't this related to the {disk|src}->discard value? Which we copied from patch 3.
So you'd just be unconditionally setting here regardless of what was configured?
The actual discard value will be used for the "format" (qcow2/raw/...) layer. QEMU always enables discard for the storage layers so that qcow2 can discard blocks from a deleted snapshot etc.