qemu/tests/qemu-iotests/199
Vladimir Sementsov-Ogievskiy 09feea6cf5 qemu-iotests/199: better catch postcopy time
The test aims to test _postcopy_ migration, and wants to do some write
operations during postcopy time.

Test considers migrate status=complete event on source as start of
postcopy. This is completely wrong, completion is completion of the
whole migration process. Let's instead consider destination start as
start of postcopy, and use RESUME event for it.

Next, as migration finish, let's use migration status=complete event on
target, as such method is closer to what libvirt or another user will
do, than tracking number of dirty-bitmaps.

Finally, add a possibility to dump events for debug. And if
set debug to True, we see, that actual postcopy period is very small
relatively to the whole test duration time (~0.2 seconds to >40 seconds
for me). This means, that test is very inefficient in what it supposed
to do. Let's improve it in following commits.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Tested-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200727194236.19551-4-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-27 15:39:58 -05:00

162 lines
5.6 KiB
Python
Executable File

#!/usr/bin/env python3
#
# Tests for dirty bitmaps postcopy migration.
#
# Copyright (c) 2016-2017 Virtuozzo International GmbH. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
import os
import iotests
from iotests import qemu_img
debug = False
disk_a = os.path.join(iotests.test_dir, 'disk_a')
disk_b = os.path.join(iotests.test_dir, 'disk_b')
size = '256G'
fifo = os.path.join(iotests.test_dir, 'mig_fifo')
def event_seconds(event):
return event['timestamp']['seconds'] + \
event['timestamp']['microseconds'] / 1000000.0
def event_dist(e1, e2):
return event_seconds(e2) - event_seconds(e1)
class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
def tearDown(self):
if debug:
self.vm_a_events += self.vm_a.get_qmp_events()
self.vm_b_events += self.vm_b.get_qmp_events()
for e in self.vm_a_events:
e['vm'] = 'SRC'
for e in self.vm_b_events:
e['vm'] = 'DST'
events = (self.vm_a_events + self.vm_b_events)
events = [(e['timestamp']['seconds'],
e['timestamp']['microseconds'],
e['vm'],
e['event'],
e.get('data', '')) for e in events]
for e in sorted(events):
print('{}.{:06} {} {} {}'.format(*e))
self.vm_a.shutdown()
self.vm_b.shutdown()
os.remove(disk_a)
os.remove(disk_b)
os.remove(fifo)
def setUp(self):
os.mkfifo(fifo)
qemu_img('create', '-f', iotests.imgfmt, disk_a, size)
qemu_img('create', '-f', iotests.imgfmt, disk_b, size)
self.vm_a = iotests.VM(path_suffix='a').add_drive(disk_a)
self.vm_b = iotests.VM(path_suffix='b').add_drive(disk_b)
self.vm_b.add_incoming("exec: cat '" + fifo + "'")
self.vm_a.launch()
self.vm_b.launch()
# collect received events for debug
self.vm_a_events = []
self.vm_b_events = []
def test_postcopy(self):
write_size = 0x40000000
granularity = 512
chunk = 4096
result = self.vm_a.qmp('block-dirty-bitmap-add', node='drive0',
name='bitmap', granularity=granularity)
self.assert_qmp(result, 'return', {})
s = 0
while s < write_size:
self.vm_a.hmp_qemu_io('drive0', 'write %d %d' % (s, chunk))
s += 0x10000
s = 0x8000
while s < write_size:
self.vm_a.hmp_qemu_io('drive0', 'write %d %d' % (s, chunk))
s += 0x10000
result = self.vm_a.qmp('x-debug-block-dirty-bitmap-sha256',
node='drive0', name='bitmap')
sha256 = result['return']['sha256']
result = self.vm_a.qmp('block-dirty-bitmap-clear', node='drive0',
name='bitmap')
self.assert_qmp(result, 'return', {})
s = 0
while s < write_size:
self.vm_a.hmp_qemu_io('drive0', 'write %d %d' % (s, chunk))
s += 0x10000
caps = [{'capability': 'dirty-bitmaps', 'state': True},
{'capability': 'events', 'state': True}]
result = self.vm_a.qmp('migrate-set-capabilities', capabilities=caps)
self.assert_qmp(result, 'return', {})
result = self.vm_b.qmp('migrate-set-capabilities', capabilities=caps)
self.assert_qmp(result, 'return', {})
result = self.vm_a.qmp('migrate', uri='exec:cat>' + fifo)
self.assert_qmp(result, 'return', {})
result = self.vm_a.qmp('migrate-start-postcopy')
self.assert_qmp(result, 'return', {})
event_resume = self.vm_b.event_wait('RESUME')
self.vm_b_events.append(event_resume)
s = 0x8000
while s < write_size:
self.vm_b.hmp_qemu_io('drive0', 'write %d %d' % (s, chunk))
s += 0x10000
match = {'data': {'status': 'completed'}}
event_complete = self.vm_b.event_wait('MIGRATION', match=match)
self.vm_b_events.append(event_complete)
# take queued event, should already been happened
event_stop = self.vm_a.event_wait('STOP')
self.vm_a_events.append(event_stop)
downtime = event_dist(event_stop, event_resume)
postcopy_time = event_dist(event_resume, event_complete)
# TODO: assert downtime * 10 < postcopy_time
if debug:
print('downtime:', downtime)
print('postcopy_time:', postcopy_time)
# Assert that bitmap migration is finished (check that successor bitmap
# is removed)
result = self.vm_b.qmp('query-block')
assert len(result['return'][0]['dirty-bitmaps']) == 1
# Check content of migrated (and updated by new writes) bitmap
result = self.vm_b.qmp('x-debug-block-dirty-bitmap-sha256',
node='drive0', name='bitmap')
self.assert_qmp(result, 'return/sha256', sha256)
if __name__ == '__main__':
iotests.main(supported_fmts=['qcow2'])