| #!/usr/bin/env python |
| # |
| # 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_img = "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 setUp(self): |
| self.vm = iotests.VM() |
| for i in range(0, self.max_drives): |
| self.vm.add_drive(self.test_img) |
| 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): |
| 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): |
| self.vm.hmp_qemu_io("drive%d" % drive, "aio_read %d %d" % |
| (i * rq_size, rq_size)) |
| |
| for i in range(wr_nr): |
| for drive in range(0, ndrives): |
| self.vm.hmp_qemu_io("drive%d" % drive, "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): |
| start_rd_bytes[i], start_rd_iops[i], start_wr_bytes[i], \ |
| start_wr_iops[i] = self.blockstats('drive%d' % i) |
| |
| self.vm.qtest("clock_step %d" % ns) |
| |
| # Read the stats after advancing the clock |
| for i in range(0, ndrives): |
| end_rd_bytes[i], end_rd_iops[i], end_wr_bytes[i], \ |
| end_wr_iops[i] = self.blockstats('drive%d' % i) |
| |
| # 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)) |
| |
| 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) |
| |
| 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) |
| |
| class ThrottleTestCoroutine(ThrottleTestCase): |
| test_img = "null-co://" |
| |
| class ThrottleTestGroupNames(iotests.QMPTestCase): |
| test_img = "null-aio://" |
| max_drives = 3 |
| |
| def setUp(self): |
| self.vm = iotests.VM() |
| for i in range(0, self.max_drives): |
| self.vm.add_drive(self.test_img, "throttling.iops-total=100") |
| 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(info.has_key('group')) |
| 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) |
| |
| |
| if __name__ == '__main__': |
| iotests.main(supported_fmts=["raw"]) |
