6bc074587a
If Cinder reports discard=true capability then add discard=unmap to disk config setting on attached volume. To have this actually provide unmap/trim support the instance must have been configured with a controller+bus type that can support it. As of now the only one known not to work is virtio-blk. In the case where we detect a configuration that will not work a warning will be logged, but the attachment will continue with the default behavior. An example of how to get a controller and bus to support this is to set the following Glance properties on an image: hw_scsi_model=virtio-scsi hw_disk_bus=scsi This feature also has some requirements for the libvirt and qemu versions being used. There is a check to ensure that libvirt is at least 1.0.6 and qemu is at least 1.6.0. If the minimum versions are not met a warning will be logged, but the attachment will continue with the default behavior. Change-Id: Icd2d20bb6906d9106df34a970b3d81b17bc3ec07 Implements: bp cinder-backend-report-discard
10 lines
447 B
YAML
10 lines
447 B
YAML
---
|
|
features:
|
|
- Add support for enabling discard support for block devices with libvirt.
|
|
This will be enabled for Cinder volume attachments that specify support
|
|
for the feature in their connection properties. This requires support to
|
|
be present in the version of libvirt (v1.0.6+) and qemu (v1.6.0+) used
|
|
along with the configured virtual drivers for the instance. The
|
|
virtio-blk driver does not support this functionality.
|
|
|