def migrate_background(
domain,
source,
destination,
migrate_params,
migrate_flags,
):
# As it seems it is possible to call multiple functions in parallel
# from different threads.
try:
domain.migrateToURI3(
MIGRATE_CONFIG.get((source.dataset_obj['os'],
destination.dataset_obj['os']))['uri'].format(
destination=destination.fqdn),
migrate_params,
migrate_flags,
)
except libvirtError as e:
if virGetLastError()[0] == VIR_ERR_OPERATION_ABORTED:
raise MigrationAborted('Migration aborted by user')
raise MigrationError(e)
def migrate_live(source, destination, vm, domain):
"""Live-migrates a VM via libvirt."""
# Reduce CPU pinning to minimum number of available cores on both
# hypervisors to avoid "invalid cpuset" errors.
props = DomainProperties.from_running(source, vm, domain)
_live_repin_cpus(
domain,
props,
min(source.dataset_obj['num_cpu'], destination.dataset_obj['num_cpu']),
)
migrate_flags = (
VIR_MIGRATE_LIVE | # Do it live
VIR_MIGRATE_PERSIST_DEST | # Define the VM on the new host
VIR_MIGRATE_CHANGE_PROTECTION | # Protect source VM
VIR_MIGRATE_NON_SHARED_DISK | # Copy non-shared storage
VIR_MIGRATE_AUTO_CONVERGE | # Slow down VM if can't migrate memory
VIR_MIGRATE_ABORT_ON_ERROR # Don't tolerate soft errors
)
migrate_params = {}
# Append OS-specific migration commands. They might not exist for some
# combinations but this should have already been checked by the caller.
migrate_flags |= MIGRATE_CONFIG.get(
(source.dataset_obj['os'], destination.dataset_obj['os']))['flags']
log.info('Starting online migration of vm {} from {} to {}'.format(
vm,
source,
destination,
))
future = parallel(
migrate_background,
args=[[
domain,
source,
destination,
migrate_params,
migrate_flags,
]],
workers=1,
return_results=False,
)[0]
try:
while future.running():
try:
js = domain.jobStats()
except libvirtError:
# When migration is finished, jobStats will fail
break
if 'memory_total' in js and 'disk_total' in js:
log.info(
('Migration progress: '
'disk {:.0f}% {:.0f}/{:.0f}MiB, '
'memory {:.0f}% {:.0f}/{:.0f}MiB, ').format(
js['disk_processed'] / (js['disk_total'] + 1) * 100,
js['disk_processed'] / 1024 / 1024,
js['disk_total'] / 1024 / 1024,
js['memory_processed'] / (js['memory_total'] + 1) *
100,
js['memory_processed'] / 1024 / 1024,
js['memory_total'] / 1024 / 1024,
))
else:
log.info('Waiting for migration stats to show up')
time.sleep(1)
except KeyboardInterrupt:
domain.abortJob()
log.info('Awaiting migration to abort')
future.result()
# Nothing to log, the function above raised an exception
else:
log.info('Awaiting migration to finish')
future.result() # Exception from slave thread will re-raise here
log.info('Migration finished')
# And pin again, in case we migrated to a host with more physical cores
domain = destination._get_domain(vm)
_live_repin_cpus(domain, props, destination.dataset_obj['num_cpu'])