qemu-e2k/docs
Avihai Horon 745c42912a vfio/migration: Add support for switchover ack capability
Loading of a VFIO device's data can take a substantial amount of time as
the device may need to allocate resources, prepare internal data
structures, etc. This can increase migration downtime, especially for
VFIO devices with a lot of resources.

To solve this, VFIO migration uAPI defines "initial bytes" as part of
its precopy data stream. Initial bytes can be used in various ways to
improve VFIO migration performance. For example, it can be used to
transfer device metadata to pre-allocate resources in the destination.
However, for this to work we need to make sure that all initial bytes
are sent and loaded in the destination before the source VM is stopped.

Use migration switchover ack capability to make sure a VFIO device's
initial bytes are sent and loaded in the destination before the source
stops the VM and attempts to complete the migration.
This can significantly reduce migration downtime for some devices.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30 06:02:51 +02:00
..
_templates
about qapi: make the vcpu parameters deprecated for 8.1 2023-06-01 11:05:05 -04:00
config
devel vfio/migration: Add support for switchover ack capability 2023-06-30 06:02:51 +02:00
interop qcow2: Explicit mention of padding bytes 2023-06-02 11:24:18 -05:00
specs virtio,pc,pci: fixes, features, cleanups 2023-04-25 09:13:27 +01:00
sphinx meson: Pass -j option to sphinx 2023-05-18 08:53:50 +02:00
sphinx-static
spin
system qemu-sparc queue 2023-06-28 15:55:54 +02:00
tools
user bsd-user: Add '-one-insn-per-tb' option equivalent to '-singlestep' 2023-05-02 15:47:40 +01:00
COLO-FT.txt migration: block incoming colo when capability is disabled 2023-05-10 18:48:12 +02:00
block-replication.txt
bypass-iommu.txt
colo-proxy.txt
conf.py Update copyright dates to 2023 2023-05-30 15:50:17 +01:00
defs.rst.inc
igd-assign.txt
image-fuzzer.txt
index.rst
memory-hotplug.txt
meson.build configure: bootstrap sphinx with mkvenv 2023-05-18 08:53:51 +02:00
multi-thread-compression.txt
multiseat.txt
nvdimm.txt
pci_expander_bridge.txt
pcie.txt
pcie_pci_bridge.txt
pcie_sriov.txt
pvrdma.txt
qcow2-cache.txt
qdev-device-use.txt
qemu-option-trace.rst.inc
qemupciserial.inf
rdma.txt
spice-port-fqdn.txt
throttle.txt
xbzrle.txt
xen-save-devices-state.txt