On Tue, 17 Nov 2015 11:14:29 +0100 Alexander Schmidt <al...@linux.vnet.ibm.com> wrote:
> Hi all, > > I started a blueprint [1] and spec [2] for enabling the usage > of native AIO mode for disk devices. The idea is to enable it > for storage backends/setups where IO performance benefits from > using native AIO mode and where no downsides are known wrt > stability or data integrity. > > As there is a wide range of storage backends and setups, I'm > looking for input on specific backends that are known to > benefit from native AIO mode (or where known problems exist). > These are the comments so far (copied from the spec): > > * native AIO mode is a bad idea if the storage is not fully > pre-allocated, e.g. for qcow2 images that grow on > demand or sparse LVM storage > * AIO mode has no effect if using the in-qemu > network clients (any disks that use <disk type='network'>). > It is only relevant if using the in-kernel network drivers > > Cases where AIO mode is beneficial > > * Raw images and pre-allocated images in qcow2 format > * Cinder volumes that are located on iSCSI, NFS or FC devices. > * Quobyte (reported by Silvan Kaiser) > > Also input on the minimum libvirt/qemu version where native > AIO mode should be used would be very helpful. > > Thanks and regards, > Alex > Adding the links... [1] https://blueprints.launchpad.net/nova/+spec/libvirt-aio-mode [2] https://review.openstack.org/#/c/232514/ __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev