Merge "XenAPI: Provide support matrix and doc for VGPU"

doc/source/admin/virtual-gpu.rst

@@ -113,7 +113,59 @@ Depending on your hypervisor:
      nvidia-35  nvidia-36  nvidia-37  nvidia-38  nvidia-39  nvidia-40  nvidia-41  nvidia-42  nvidia-43  nvidia-44  nvidia-45
 
 
-.. todo:: Discovering GPU types in Xen.
+- For XenServer, virtual GPU types are created by XenServer at startup
+  depending on the available hardware and config files present in dom0.
+  You can run the command of ``xe vgpu-type-list`` from dom0 to get the
+  available vGPU types. The value for the field of ``model-name ( RO):``
+  is the vGPU type's name which can be used to set the nova config option
+  ``[devices]/enabled_vgpu_types``. See the following example:
+
+  .. code-block:: console
+
+    [root@trailblazer-2 ~]# xe vgpu-type-list
+    uuid ( RO)              : 78d2d963-41d6-4130-8842-aedbc559709f
+           vendor-name ( RO): NVIDIA Corporation
+            model-name ( RO): GRID M60-8Q
+             max-heads ( RO): 4
+        max-resolution ( RO): 4096x2160
+
+
+    uuid ( RO)              : a1bb1692-8ce3-4577-a611-6b4b8f35a5c9
+           vendor-name ( RO): NVIDIA Corporation
+            model-name ( RO): GRID M60-0Q
+             max-heads ( RO): 2
+        max-resolution ( RO): 2560x1600
+
+
+    uuid ( RO)              : 69d03200-49eb-4002-b661-824aec4fd26f
+           vendor-name ( RO): NVIDIA Corporation
+            model-name ( RO): GRID M60-2A
+             max-heads ( RO): 1
+        max-resolution ( RO): 1280x1024
+
+
+    uuid ( RO)              : c58b1007-8b47-4336-95aa-981a5634d03d
+           vendor-name ( RO): NVIDIA Corporation
+            model-name ( RO): GRID M60-4Q
+             max-heads ( RO): 4
+        max-resolution ( RO): 4096x2160
+
+
+    uuid ( RO)              : 292a2b20-887f-4a13-b310-98a75c53b61f
+           vendor-name ( RO): NVIDIA Corporation
+            model-name ( RO): GRID M60-2Q
+             max-heads ( RO): 4
+        max-resolution ( RO): 4096x2160
+
+
+    uuid ( RO)              : d377db6b-a068-4a98-92a8-f94bd8d6cc5d
+           vendor-name ( RO): NVIDIA Corporation
+            model-name ( RO): GRID M60-0B
+             max-heads ( RO): 2
+        max-resolution ( RO): 2560x1600
+
+    ...
+
 
 Caveats
 -------
@@ -147,7 +199,26 @@ For libvirt:
   instance immediately after rescue. However, rebuilding the rescued instance
   only helps if there are other free vGPUs on the host.
 
-.. todo:: Xen caveats.
+For XenServer:
+
+* Suspend and live migration with vGPUs attached depends on support from the
+  underlying XenServer version. Please see XenServer release notes for up to
+  date information on when a hypervisor supporting live migration and
+  suspend/resume with vGPUs is available. If a suspend or live migrate operation
+  is attempted with a XenServer version that does not support that operation, an
+  internal exception will occur that will cause nova setting the instance to
+  be in ERROR status. You can use the command of
+  ``openstack server set --state active <server>`` to set it back to ACTIVE.
+
+* Resizing an instance with a new flavor that has vGPU resources doesn't
+  allocate those vGPUs to the instance (the instance is created without
+  vGPU resources). The proposed workaround is to rebuild the instance after
+  resizing it. The rebuild operation allocates vGPUS to the instance.
+
+* Cold migrating an instance to another host will have the same problem as
+  resize. If you want to migrate an instance, make sure to rebuild it after the
+  migration.
+
 
 .. Links
 .. _Intel GVT-g: https://01.org/igvt-g