| #!/usr/bin/env python3 | |
| # group: throttle | |
| # | |
| # Tests for IO throttling | |
| # | |
| # Copyright (C) 2015 Red Hat, Inc. | |
| # Copyright (C) 2015-2016 Igalia, S.L. | |
| # | |
| # 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 iotests | |
| nsec_per_sec = 1000000000 | |
| class ThrottleTestCase(iotests.QMPTestCase): | |
| test_driver = "null-aio" | |
| max_drives = 3 | |
| def blockstats(self, device): | |
| result = self.vm.qmp("query-blockstats") | |
| for r in result['return']: | |
| if r['device'] == device: | |
| stat = r['stats'] | |
| return stat['rd_bytes'], stat['rd_operations'], stat['wr_bytes'], stat['wr_operations'] | |
| raise Exception("Device not found for blockstats: %s" % device) | |
| def required_drivers(self): | |
| return [self.test_driver] | |
| @iotests.skip_if_unsupported(required_drivers) | |
| def setUp(self): | |
| self.vm = iotests.VM() | |
| for i in range(0, self.max_drives): | |
| self.vm.add_drive(self.test_driver + "://", "file.read-zeroes=on") | |
| self.vm.launch() | |
| def tearDown(self): | |
| self.vm.shutdown() | |
| def configure_throttle(self, ndrives, params): | |
| params['group'] = 'test' | |
| # Set the I/O throttling parameters to all drives | |
| for i in range(0, ndrives): | |
| params['device'] = 'drive%d' % i | |
| self.vm.cmd("block_set_io_throttle", conv_keys=False, **params) | |
| def do_test_throttle(self, ndrives, seconds, params, first_drive = 0): | |
| def check_limit(limit, num): | |
| # IO throttling algorithm is discrete, allow 10% error so the test | |
| # is more robust | |
| return limit == 0 or \ | |
| (num < seconds * limit * 1.1 / ndrives | |
| and num > seconds * limit * 0.9 / ndrives) | |
| # Set vm clock to a known value | |
| ns = seconds * nsec_per_sec | |
| self.vm.qtest("clock_step %d" % ns) | |
| # Submit enough requests so the throttling mechanism kicks | |
| # in. The throttled requests won't be executed until we | |
| # advance the virtual clock. | |
| rq_size = 512 | |
| rd_nr = max(params['bps'] // rq_size // 2, | |
| params['bps_rd'] // rq_size, | |
| params['iops'] // 2, | |
| params['iops_rd']) | |
| rd_nr *= seconds * 2 | |
| rd_nr //= ndrives | |
| wr_nr = max(params['bps'] // rq_size // 2, | |
| params['bps_wr'] // rq_size, | |
| params['iops'] // 2, | |
| params['iops_wr']) | |
| wr_nr *= seconds * 2 | |
| wr_nr //= ndrives | |
| # Send I/O requests to all drives | |
| for i in range(rd_nr): | |
| for drive in range(0, ndrives): | |
| idx = first_drive + drive | |
| self.vm.hmp_qemu_io("drive%d" % idx, "aio_read %d %d" % | |
| (i * rq_size, rq_size)) | |
| for i in range(wr_nr): | |
| for drive in range(0, ndrives): | |
| idx = first_drive + drive | |
| self.vm.hmp_qemu_io("drive%d" % idx, "aio_write %d %d" % | |
| (i * rq_size, rq_size)) | |
| # We'll store the I/O stats for each drive in these arrays | |
| start_rd_bytes = [0] * ndrives | |
| start_rd_iops = [0] * ndrives | |
| start_wr_bytes = [0] * ndrives | |
| start_wr_iops = [0] * ndrives | |
| end_rd_bytes = [0] * ndrives | |
| end_rd_iops = [0] * ndrives | |
| end_wr_bytes = [0] * ndrives | |
| end_wr_iops = [0] * ndrives | |
| # Read the stats before advancing the clock | |
| for i in range(0, ndrives): | |
| idx = first_drive + i | |
| start_rd_bytes[i], start_rd_iops[i], start_wr_bytes[i], \ | |
| start_wr_iops[i] = self.blockstats('drive%d' % idx) | |
| self.vm.qtest("clock_step %d" % ns) | |
| # Read the stats after advancing the clock | |
| for i in range(0, ndrives): | |
| idx = first_drive + i | |
| end_rd_bytes[i], end_rd_iops[i], end_wr_bytes[i], \ | |
| end_wr_iops[i] = self.blockstats('drive%d' % idx) | |
| # Check that the I/O is within the limits and evenly distributed | |
| for i in range(0, ndrives): | |
| rd_bytes = end_rd_bytes[i] - start_rd_bytes[i] | |
| rd_iops = end_rd_iops[i] - start_rd_iops[i] | |
| wr_bytes = end_wr_bytes[i] - start_wr_bytes[i] | |
| wr_iops = end_wr_iops[i] - start_wr_iops[i] | |
| self.assertTrue(check_limit(params['bps'], rd_bytes + wr_bytes)) | |
| self.assertTrue(check_limit(params['bps_rd'], rd_bytes)) | |
| self.assertTrue(check_limit(params['bps_wr'], wr_bytes)) | |
| self.assertTrue(check_limit(params['iops'], rd_iops + wr_iops)) | |
| self.assertTrue(check_limit(params['iops_rd'], rd_iops)) | |
| self.assertTrue(check_limit(params['iops_wr'], wr_iops)) | |
| # Allow remaining requests to finish. We submitted twice as many to | |
| # ensure the throttle limit is reached. | |
| self.vm.qtest("clock_step %d" % ns) | |
| # Connect N drives to a VM and test I/O in all of them | |
| def test_all(self): | |
| params = {"bps": 4096, | |
| "bps_rd": 4096, | |
| "bps_wr": 4096, | |
| "iops": 10, | |
| "iops_rd": 10, | |
| "iops_wr": 10, | |
| } | |
| # Repeat the test with different numbers of drives | |
| for ndrives in range(1, self.max_drives + 1): | |
| # Pick each out of all possible params and test | |
| for tk in params: | |
| limits = dict([(k, 0) for k in params]) | |
| limits[tk] = params[tk] * ndrives | |
| self.configure_throttle(ndrives, limits) | |
| self.do_test_throttle(ndrives, 5, limits) | |
| # Connect N drives to a VM and test I/O in just one of them a time | |
| def test_one(self): | |
| params = {"bps": 4096, | |
| "bps_rd": 4096, | |
| "bps_wr": 4096, | |
| "iops": 10, | |
| "iops_rd": 10, | |
| "iops_wr": 10, | |
| } | |
| # Repeat the test for each one of the drives | |
| for drive in range(0, self.max_drives): | |
| # Pick each out of all possible params and test | |
| for tk in params: | |
| limits = dict([(k, 0) for k in params]) | |
| limits[tk] = params[tk] * self.max_drives | |
| self.configure_throttle(self.max_drives, limits) | |
| self.do_test_throttle(1, 5, limits, drive) | |
| def test_burst(self): | |
| params = {"bps": 4096, | |
| "bps_rd": 4096, | |
| "bps_wr": 4096, | |
| "iops": 10, | |
| "iops_rd": 10, | |
| "iops_wr": 10, | |
| } | |
| ndrives = 1 | |
| # Pick each out of all possible params and test | |
| for tk in params: | |
| rate = params[tk] * ndrives | |
| burst_rate = rate * 7 | |
| burst_length = 4 | |
| # Configure the throttling settings | |
| settings = dict([(k, 0) for k in params]) | |
| settings[tk] = rate | |
| settings['%s_max' % tk] = burst_rate | |
| settings['%s_max_length' % tk] = burst_length | |
| self.configure_throttle(ndrives, settings) | |
| # Wait for the bucket to empty so we can do bursts | |
| wait_ns = nsec_per_sec * burst_length * burst_rate // rate | |
| self.vm.qtest("clock_step %d" % wait_ns) | |
| # Test I/O at the max burst rate | |
| limits = dict([(k, 0) for k in params]) | |
| limits[tk] = burst_rate | |
| self.do_test_throttle(ndrives, burst_length, limits) | |
| # Now test I/O at the normal rate | |
| limits[tk] = rate | |
| self.do_test_throttle(ndrives, 5, limits) | |
| # Test that removing a drive from a throttle group should not | |
| # affect the remaining members of the group. | |
| # https://bugzilla.redhat.com/show_bug.cgi?id=1535914 | |
| def test_remove_group_member(self): | |
| # Create a throttle group with two drives | |
| # and set a 4 KB/s read limit. | |
| params = {"bps": 0, | |
| "bps_rd": 4096, | |
| "bps_wr": 0, | |
| "iops": 0, | |
| "iops_rd": 0, | |
| "iops_wr": 0 } | |
| self.configure_throttle(2, params) | |
| # Read 4KB from drive0. This is performed immediately. | |
| self.vm.hmp_qemu_io("drive0", "aio_read 0 4096") | |
| # Read 2KB. The I/O limit has been exceeded so this | |
| # request is throttled and a timer is set to wake it up. | |
| self.vm.hmp_qemu_io("drive0", "aio_read 0 2048") | |
| # Read 2KB again. We're still over the I/O limit so this is | |
| # request is also throttled, but no new timer is set since | |
| # there's already one. | |
| self.vm.hmp_qemu_io("drive0", "aio_read 0 2048") | |
| # Read from drive1. This request is also throttled, and no | |
| # timer is set in drive1 because there's already one in | |
| # drive0. | |
| self.vm.hmp_qemu_io("drive1", "aio_read 0 4096") | |
| # At this point only the first 4KB have been read from drive0. | |
| # The other requests are throttled. | |
| self.assertEqual(self.blockstats('drive0')[0], 4096) | |
| self.assertEqual(self.blockstats('drive1')[0], 0) | |
| # Remove drive0 from the throttle group and disable its I/O limits. | |
| # drive1 remains in the group with a throttled request. | |
| params['bps_rd'] = 0 | |
| params['device'] = 'drive0' | |
| self.vm.cmd("block_set_io_throttle", conv_keys=False, **params) | |
| # Removing the I/O limits from drive0 drains its two pending requests. | |
| # The read request in drive1 is still throttled. | |
| self.assertEqual(self.blockstats('drive0')[0], 8192) | |
| self.assertEqual(self.blockstats('drive1')[0], 0) | |
| # Advance the clock 5 seconds. This completes the request in drive1 | |
| self.vm.qtest("clock_step %d" % (5 * nsec_per_sec)) | |
| # Now all requests have been processed. | |
| self.assertEqual(self.blockstats('drive0')[0], 8192) | |
| self.assertEqual(self.blockstats('drive1')[0], 4096) | |
| class ThrottleTestCoroutine(ThrottleTestCase): | |
| test_driver = "null-co" | |
| class ThrottleTestGroupNames(iotests.QMPTestCase): | |
| max_drives = 3 | |
| def setUp(self): | |
| self.vm = iotests.VM() | |
| for i in range(0, self.max_drives): | |
| self.vm.add_drive("null-co://", | |
| "throttling.iops-total=100,file.read-zeroes=on") | |
| self.vm.launch() | |
| def tearDown(self): | |
| self.vm.shutdown() | |
| def set_io_throttle(self, device, params): | |
| params["device"] = device | |
| self.vm.cmd("block_set_io_throttle", conv_keys=False, **params) | |
| def verify_name(self, device, name): | |
| result = self.vm.qmp("query-block") | |
| for r in result["return"]: | |
| if r["device"] == device: | |
| info = r["inserted"] | |
| if name: | |
| self.assertEqual(info["group"], name) | |
| else: | |
| self.assertFalse('group' in info) | |
| return | |
| raise Exception("No group information found for '%s'" % device) | |
| def test_group_naming(self): | |
| params = {"bps": 0, | |
| "bps_rd": 0, | |
| "bps_wr": 0, | |
| "iops": 0, | |
| "iops_rd": 0, | |
| "iops_wr": 0} | |
| # Check the drives added using the command line. | |
| # The default throttling group name is the device name. | |
| for i in range(self.max_drives): | |
| devname = "drive%d" % i | |
| self.verify_name(devname, devname) | |
| # Clear throttling settings => the group name is gone. | |
| for i in range(self.max_drives): | |
| devname = "drive%d" % i | |
| self.set_io_throttle(devname, params) | |
| self.verify_name(devname, None) | |
| # Set throttling settings using block_set_io_throttle and | |
| # check the default group names. | |
| params["iops"] = 10 | |
| for i in range(self.max_drives): | |
| devname = "drive%d" % i | |
| self.set_io_throttle(devname, params) | |
| self.verify_name(devname, devname) | |
| # Set a custom group name for each device | |
| for i in range(3): | |
| devname = "drive%d" % i | |
| groupname = "group%d" % i | |
| params['group'] = groupname | |
| self.set_io_throttle(devname, params) | |
| self.verify_name(devname, groupname) | |
| # Put drive0 in group1 and check that all other devices remain | |
| # unchanged | |
| params['group'] = 'group1' | |
| self.set_io_throttle('drive0', params) | |
| self.verify_name('drive0', 'group1') | |
| for i in range(1, self.max_drives): | |
| devname = "drive%d" % i | |
| groupname = "group%d" % i | |
| self.verify_name(devname, groupname) | |
| # Put drive0 in group2 and check that all other devices remain | |
| # unchanged | |
| params['group'] = 'group2' | |
| self.set_io_throttle('drive0', params) | |
| self.verify_name('drive0', 'group2') | |
| for i in range(1, self.max_drives): | |
| devname = "drive%d" % i | |
| groupname = "group%d" % i | |
| self.verify_name(devname, groupname) | |
| # Clear throttling settings from drive0 check that all other | |
| # devices remain unchanged | |
| params["iops"] = 0 | |
| self.set_io_throttle('drive0', params) | |
| self.verify_name('drive0', None) | |
| for i in range(1, self.max_drives): | |
| devname = "drive%d" % i | |
| groupname = "group%d" % i | |
| self.verify_name(devname, groupname) | |
| class ThrottleTestRemovableMedia(iotests.QMPTestCase): | |
| def setUp(self): | |
| self.vm = iotests.VM() | |
| self.vm.add_device("{},id=virtio-scsi".format('virtio-scsi')) | |
| self.vm.launch() | |
| def tearDown(self): | |
| self.vm.shutdown() | |
| def test_removable_media(self): | |
| # Add a couple of dummy nodes named cd0 and cd1 | |
| self.vm.cmd("blockdev-add", driver="null-co", | |
| read_zeroes=True, node_name="cd0") | |
| self.vm.cmd("blockdev-add", driver="null-co", | |
| read_zeroes=True, node_name="cd1") | |
| # Attach a CD drive with cd0 inserted | |
| self.vm.cmd("device_add", driver="scsi-cd", | |
| id="dev0", drive="cd0") | |
| # Set I/O limits | |
| args = { "id": "dev0", "iops": 100, "iops_rd": 0, "iops_wr": 0, | |
| "bps": 50, "bps_rd": 0, "bps_wr": 0 } | |
| self.vm.cmd("block_set_io_throttle", conv_keys=False, **args) | |
| # Check that the I/O limits have been set | |
| result = self.vm.qmp("query-block") | |
| self.assert_qmp(result, 'return[0]/inserted/iops', 100) | |
| self.assert_qmp(result, 'return[0]/inserted/bps', 50) | |
| # Now eject cd0 and insert cd1 | |
| self.vm.cmd("blockdev-open-tray", id='dev0') | |
| self.vm.cmd("blockdev-remove-medium", id='dev0') | |
| self.vm.cmd("blockdev-insert-medium", id='dev0', node_name='cd1') | |
| # Check that the I/O limits are still the same | |
| result = self.vm.qmp("query-block") | |
| self.assert_qmp(result, 'return[0]/inserted/iops', 100) | |
| self.assert_qmp(result, 'return[0]/inserted/bps', 50) | |
| # Eject cd1 | |
| self.vm.cmd("blockdev-remove-medium", id='dev0') | |
| # Check that we can't set limits if the device has no medium | |
| result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **args) | |
| self.assert_qmp(result, 'error/class', 'GenericError') | |
| # Remove the CD drive | |
| self.vm.cmd("device_del", id='dev0') | |
| if __name__ == '__main__': | |
| if 'null-co' not in iotests.supported_formats(): | |
| iotests.notrun('null-co driver support missing') | |
| iotests.main(supported_fmts=["raw"]) |