Reference: fate#315125: Set NOCOW flag to newly created volume by default, to solve performance issue on btrfs. Signed-off-by: Chunyan Liu Index: virt-manager-2.0.0/virtinst/storage.py =================================================================== --- virt-manager-2.0.0.orig/virtinst/storage.py +++ virt-manager-2.0.0/virtinst/storage.py @@ -618,6 +618,11 @@ class StorageVolume(_StorageObject): return self._pool_xml.get_disk_type() file_type = property(_get_vol_type) + def _nocow_default_cb(self): + return self.conn.check_support( + self.conn.SUPPORT_CONN_NOCOW) + nocow = XMLProperty("./target/nocow", is_bool=True) + ################## # XML properties # Index: virt-manager-2.0.0/virtinst/support.py =================================================================== --- virt-manager-2.0.0.orig/virtinst/support.py +++ virt-manager-2.0.0/virtinst/support.py @@ -267,6 +267,8 @@ SUPPORT_CONN_USB3_PORTS = _make(version= SUPPORT_CONN_MACHVIRT_PCI_DEFAULT = _make(version="3.0.0") SUPPORT_CONN_QEMU_XHCI = _make(version="3.3.0", hv_version={"qemu": "2.9.0"}) SUPPORT_CONN_VNC_NONE_AUTH = _make(hv_version={"qemu": "2.9.0"}) +SUPPORT_CONN_NOCOW = _make( + version="1.2.18", hv_version={"qemu": "2.2.0", "test": 0}) # We choose qemu 2.11.0 as the first version to target for q35 default. # That's not really based on anything except reasonably modern at the