| #!/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 |
| result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params) |
| self.assert_qmp(result, 'return', {}) |
| |
| 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' |
| result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params) |
| self.assert_qmp(result, 'return', {}) |
| |
| # 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 |
| result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params) |
| self.assert_qmp(result, 'return', {}) |
| |
| 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( |
| iotests.get_virtio_scsi_device())) |
| self.vm.launch() |
| |
| def tearDown(self): |
| self.vm.shutdown() |
| |
| def test_removable_media(self): |
| # Add a couple of dummy nodes named cd0 and cd1 |
| result = self.vm.qmp("blockdev-add", driver="null-co", |
| read_zeroes=True, node_name="cd0") |
| self.assert_qmp(result, 'return', {}) |
| result = self.vm.qmp("blockdev-add", driver="null-co", |
| read_zeroes=True, node_name="cd1") |
| self.assert_qmp(result, 'return', {}) |
| |
| # Attach a CD drive with cd0 inserted |
| result = self.vm.qmp("device_add", driver="scsi-cd", |
| id="dev0", drive="cd0") |
| self.assert_qmp(result, 'return', {}) |
| |
| # Set I/O limits |
| args = { "id": "dev0", "iops": 100, "iops_rd": 0, "iops_wr": 0, |
| "bps": 50, "bps_rd": 0, "bps_wr": 0 } |
| result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **args) |
| self.assert_qmp(result, 'return', {}) |
| |
| # 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 |
| result = self.vm.qmp("blockdev-open-tray", id='dev0') |
| self.assert_qmp(result, 'return', {}) |
| result = self.vm.qmp("blockdev-remove-medium", id='dev0') |
| self.assert_qmp(result, 'return', {}) |
| result = self.vm.qmp("blockdev-insert-medium", id='dev0', node_name='cd1') |
| self.assert_qmp(result, 'return', {}) |
| |
| # 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 |
| result = self.vm.qmp("blockdev-remove-medium", id='dev0') |
| self.assert_qmp(result, 'return', {}) |
| |
| # 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 |
| result = self.vm.qmp("device_del", id='dev0') |
| self.assert_qmp(result, 'return', {}) |
| |
| |
| if __name__ == '__main__': |
| if 'null-co' not in iotests.supported_formats(): |
| iotests.notrun('null-co driver support missing') |
| iotests.main(supported_fmts=["raw"]) |
