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