Re: [libvirt PATCH 3/6] docs: introduces new vhostuser disk type
On Tue, Feb 02, 2021 at 16:04:09 +0100, Pavel Hrdina wrote:
<disk type='vhostuser' device='disk'>
<driver name='qemu' type='raw'/>
<source type='unix' path='/tmp/vhost-blk.sock'
mode='client'>
<reconnect enabled='yes' timeout='10'/>
</source>
<target dev='vda' bus='virtio'/>
</disk>
Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com>
---
docs/formatdomain.rst | 32 ++++++++++++++++++++++++++++++--
docs/schemas/domaincommon.rng | 19 +++++++++++++++++++
2 files changed, 49 insertions(+), 2 deletions(-)
[...]
@@ -2581,6 +2588,18 @@ paravirtualized driver is specified via the
``disk`` element.
is not involved (compared to passing say ``/dev/nvme0n1`` via
``<disk type='block'>`` and therefore lower latencies can be
achieved.
+ ``vhostuser``
+ Enables the hypervisor to connect to another process using vhost-user
+ protocol. Requires shared memory configured for the VM, for more details
+ see ``access`` mode for `memoryBacking <#elementsMemoryBacking>` element.
Here we are missing a lot of the caveats of a vhostuser backed disk. A
blanked disclaimer such as:
"Note that the vhost server replaces both the disk frontend and backend
thus almost all of the disk properties can't be configured via the
<disk> XML for this disk type. Additionally features such as blockjobs,
incremental backups and snapshots are not supported for this disk type."
Should do it.