38 lines
1.2 KiB
ReStructuredText
38 lines
1.2 KiB
ReStructuredText
=============
|
|
D-Bus VMState
|
|
=============
|
|
|
|
The QEMU dbus-vmstate object's aim is to migrate helpers' data running
|
|
on a QEMU D-Bus bus. (refer to the :doc:`dbus` document for
|
|
some recommendations on D-Bus usage)
|
|
|
|
Upon migration, QEMU will go through the queue of
|
|
``org.qemu.VMState1`` D-Bus name owners and query their ``Id``. It
|
|
must be unique among the helpers.
|
|
|
|
It will then save arbitrary data of each Id to be transferred in the
|
|
migration stream and restored/loaded at the corresponding destination
|
|
helper.
|
|
|
|
For now, the data amount to be transferred is arbitrarily limited to
|
|
1Mb. The state must be saved quickly (a fraction of a second). (D-Bus
|
|
imposes a time limit on reply anyway, and migration would fail if data
|
|
isn't given quickly enough.)
|
|
|
|
dbus-vmstate object can be configured with the expected list of
|
|
helpers by setting its ``id-list`` property, with a comma-separated
|
|
``Id`` list.
|
|
|
|
.. only:: sphinx4
|
|
|
|
.. dbus-doc:: backends/dbus-vmstate1.xml
|
|
|
|
.. only:: not sphinx4
|
|
|
|
.. warning::
|
|
Sphinx 4 is required to build D-Bus documentation.
|
|
|
|
This is the content of ``backends/dbus-vmstate1.xml``:
|
|
|
|
.. literalinclude:: ../../backends/dbus-vmstate1.xml
|
|
:language: xml
|