xref: /openbmc/qemu/tests/qemu-iotests/093 (revision b91a0fa7)
1#!/usr/bin/env python3
2# group: throttle
3#
4# Tests for IO throttling
5#
6# Copyright (C) 2015 Red Hat, Inc.
7# Copyright (C) 2015-2016 Igalia, S.L.
8#
9# This program is free software; you can redistribute it and/or modify
10# it under the terms of the GNU General Public License as published by
11# the Free Software Foundation; either version 2 of the License, or
12# (at your option) any later version.
13#
14# This program is distributed in the hope that it will be useful,
15# but WITHOUT ANY WARRANTY; without even the implied warranty of
16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17# GNU General Public License for more details.
18#
19# You should have received a copy of the GNU General Public License
20# along with this program.  If not, see <http://www.gnu.org/licenses/>.
21#
22
23import iotests
24
25nsec_per_sec = 1000000000
26
27class ThrottleTestCase(iotests.QMPTestCase):
28    test_driver = "null-aio"
29    max_drives = 3
30
31    def blockstats(self, device):
32        result = self.vm.qmp("query-blockstats")
33        for r in result['return']:
34            if r['device'] == device:
35                stat = r['stats']
36                return stat['rd_bytes'], stat['rd_operations'], stat['wr_bytes'], stat['wr_operations']
37        raise Exception("Device not found for blockstats: %s" % device)
38
39    def required_drivers(self):
40        return [self.test_driver]
41
42    @iotests.skip_if_unsupported(required_drivers)
43    def setUp(self):
44        self.vm = iotests.VM()
45        for i in range(0, self.max_drives):
46            self.vm.add_drive(self.test_driver + "://", "file.read-zeroes=on")
47        self.vm.launch()
48
49    def tearDown(self):
50        self.vm.shutdown()
51
52    def configure_throttle(self, ndrives, params):
53        params['group'] = 'test'
54
55        # Set the I/O throttling parameters to all drives
56        for i in range(0, ndrives):
57            params['device'] = 'drive%d' % i
58            result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
59            self.assert_qmp(result, 'return', {})
60
61    def do_test_throttle(self, ndrives, seconds, params, first_drive = 0):
62        def check_limit(limit, num):
63            # IO throttling algorithm is discrete, allow 10% error so the test
64            # is more robust
65            return limit == 0 or \
66                   (num < seconds * limit * 1.1 / ndrives
67                   and num > seconds * limit * 0.9 / ndrives)
68
69        # Set vm clock to a known value
70        ns = seconds * nsec_per_sec
71        self.vm.qtest("clock_step %d" % ns)
72
73        # Submit enough requests so the throttling mechanism kicks
74        # in. The throttled requests won't be executed until we
75        # advance the virtual clock.
76        rq_size = 512
77        rd_nr = max(params['bps'] // rq_size // 2,
78                    params['bps_rd'] // rq_size,
79                    params['iops'] // 2,
80                    params['iops_rd'])
81        rd_nr *= seconds * 2
82        rd_nr //= ndrives
83        wr_nr = max(params['bps'] // rq_size // 2,
84                    params['bps_wr'] // rq_size,
85                    params['iops'] // 2,
86                    params['iops_wr'])
87        wr_nr *= seconds * 2
88        wr_nr //= ndrives
89
90        # Send I/O requests to all drives
91        for i in range(rd_nr):
92            for drive in range(0, ndrives):
93                idx = first_drive + drive
94                self.vm.hmp_qemu_io("drive%d" % idx, "aio_read %d %d" %
95                                    (i * rq_size, rq_size))
96
97        for i in range(wr_nr):
98            for drive in range(0, ndrives):
99                idx = first_drive + drive
100                self.vm.hmp_qemu_io("drive%d" % idx, "aio_write %d %d" %
101                                    (i * rq_size, rq_size))
102
103        # We'll store the I/O stats for each drive in these arrays
104        start_rd_bytes = [0] * ndrives
105        start_rd_iops  = [0] * ndrives
106        start_wr_bytes = [0] * ndrives
107        start_wr_iops  = [0] * ndrives
108        end_rd_bytes   = [0] * ndrives
109        end_rd_iops    = [0] * ndrives
110        end_wr_bytes   = [0] * ndrives
111        end_wr_iops    = [0] * ndrives
112
113        # Read the stats before advancing the clock
114        for i in range(0, ndrives):
115            idx = first_drive + i
116            start_rd_bytes[i], start_rd_iops[i], start_wr_bytes[i], \
117                start_wr_iops[i] = self.blockstats('drive%d' % idx)
118
119        self.vm.qtest("clock_step %d" % ns)
120
121        # Read the stats after advancing the clock
122        for i in range(0, ndrives):
123            idx = first_drive + i
124            end_rd_bytes[i], end_rd_iops[i], end_wr_bytes[i], \
125                end_wr_iops[i] = self.blockstats('drive%d' % idx)
126
127        # Check that the I/O is within the limits and evenly distributed
128        for i in range(0, ndrives):
129            rd_bytes = end_rd_bytes[i] - start_rd_bytes[i]
130            rd_iops = end_rd_iops[i] - start_rd_iops[i]
131            wr_bytes = end_wr_bytes[i] - start_wr_bytes[i]
132            wr_iops = end_wr_iops[i] - start_wr_iops[i]
133
134            self.assertTrue(check_limit(params['bps'], rd_bytes + wr_bytes))
135            self.assertTrue(check_limit(params['bps_rd'], rd_bytes))
136            self.assertTrue(check_limit(params['bps_wr'], wr_bytes))
137            self.assertTrue(check_limit(params['iops'], rd_iops + wr_iops))
138            self.assertTrue(check_limit(params['iops_rd'], rd_iops))
139            self.assertTrue(check_limit(params['iops_wr'], wr_iops))
140
141        # Allow remaining requests to finish.  We submitted twice as many to
142        # ensure the throttle limit is reached.
143        self.vm.qtest("clock_step %d" % ns)
144
145    # Connect N drives to a VM and test I/O in all of them
146    def test_all(self):
147        params = {"bps": 4096,
148                  "bps_rd": 4096,
149                  "bps_wr": 4096,
150                  "iops": 10,
151                  "iops_rd": 10,
152                  "iops_wr": 10,
153                 }
154        # Repeat the test with different numbers of drives
155        for ndrives in range(1, self.max_drives + 1):
156            # Pick each out of all possible params and test
157            for tk in params:
158                limits = dict([(k, 0) for k in params])
159                limits[tk] = params[tk] * ndrives
160                self.configure_throttle(ndrives, limits)
161                self.do_test_throttle(ndrives, 5, limits)
162
163    # Connect N drives to a VM and test I/O in just one of them a time
164    def test_one(self):
165        params = {"bps": 4096,
166                  "bps_rd": 4096,
167                  "bps_wr": 4096,
168                  "iops": 10,
169                  "iops_rd": 10,
170                  "iops_wr": 10,
171                 }
172        # Repeat the test for each one of the drives
173        for drive in range(0, self.max_drives):
174            # Pick each out of all possible params and test
175            for tk in params:
176                limits = dict([(k, 0) for k in params])
177                limits[tk] = params[tk] * self.max_drives
178                self.configure_throttle(self.max_drives, limits)
179                self.do_test_throttle(1, 5, limits, drive)
180
181    def test_burst(self):
182        params = {"bps": 4096,
183                  "bps_rd": 4096,
184                  "bps_wr": 4096,
185                  "iops": 10,
186                  "iops_rd": 10,
187                  "iops_wr": 10,
188                 }
189        ndrives = 1
190        # Pick each out of all possible params and test
191        for tk in params:
192            rate = params[tk] * ndrives
193            burst_rate = rate * 7
194            burst_length = 4
195
196            # Configure the throttling settings
197            settings = dict([(k, 0) for k in params])
198            settings[tk] = rate
199            settings['%s_max' % tk] = burst_rate
200            settings['%s_max_length' % tk] = burst_length
201            self.configure_throttle(ndrives, settings)
202
203            # Wait for the bucket to empty so we can do bursts
204            wait_ns = nsec_per_sec * burst_length * burst_rate // rate
205            self.vm.qtest("clock_step %d" % wait_ns)
206
207            # Test I/O at the max burst rate
208            limits = dict([(k, 0) for k in params])
209            limits[tk] = burst_rate
210            self.do_test_throttle(ndrives, burst_length, limits)
211
212            # Now test I/O at the normal rate
213            limits[tk] = rate
214            self.do_test_throttle(ndrives, 5, limits)
215
216    # Test that removing a drive from a throttle group should not
217    # affect the remaining members of the group.
218    # https://bugzilla.redhat.com/show_bug.cgi?id=1535914
219    def test_remove_group_member(self):
220        # Create a throttle group with two drives
221        # and set a 4 KB/s read limit.
222        params = {"bps": 0,
223                  "bps_rd": 4096,
224                  "bps_wr": 0,
225                  "iops": 0,
226                  "iops_rd": 0,
227                  "iops_wr": 0 }
228        self.configure_throttle(2, params)
229
230        # Read 4KB from drive0. This is performed immediately.
231        self.vm.hmp_qemu_io("drive0", "aio_read 0 4096")
232
233        # Read 2KB. The I/O limit has been exceeded so this
234        # request is throttled and a timer is set to wake it up.
235        self.vm.hmp_qemu_io("drive0", "aio_read 0 2048")
236
237        # Read 2KB again. We're still over the I/O limit so this is
238        # request is also throttled, but no new timer is set since
239        # there's already one.
240        self.vm.hmp_qemu_io("drive0", "aio_read 0 2048")
241
242        # Read from drive1. This request is also throttled, and no
243        # timer is set in drive1 because there's already one in
244        # drive0.
245        self.vm.hmp_qemu_io("drive1", "aio_read 0 4096")
246
247        # At this point only the first 4KB have been read from drive0.
248        # The other requests are throttled.
249        self.assertEqual(self.blockstats('drive0')[0], 4096)
250        self.assertEqual(self.blockstats('drive1')[0], 0)
251
252        # Remove drive0 from the throttle group and disable its I/O limits.
253        # drive1 remains in the group with a throttled request.
254        params['bps_rd'] = 0
255        params['device'] = 'drive0'
256        result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
257        self.assert_qmp(result, 'return', {})
258
259        # Removing the I/O limits from drive0 drains its two pending requests.
260        # The read request in drive1 is still throttled.
261        self.assertEqual(self.blockstats('drive0')[0], 8192)
262        self.assertEqual(self.blockstats('drive1')[0], 0)
263
264        # Advance the clock 5 seconds. This completes the request in drive1
265        self.vm.qtest("clock_step %d" % (5 * nsec_per_sec))
266
267        # Now all requests have been processed.
268        self.assertEqual(self.blockstats('drive0')[0], 8192)
269        self.assertEqual(self.blockstats('drive1')[0], 4096)
270
271class ThrottleTestCoroutine(ThrottleTestCase):
272    test_driver = "null-co"
273
274class ThrottleTestGroupNames(iotests.QMPTestCase):
275    max_drives = 3
276
277    def setUp(self):
278        self.vm = iotests.VM()
279        for i in range(0, self.max_drives):
280            self.vm.add_drive("null-co://",
281                              "throttling.iops-total=100,file.read-zeroes=on")
282        self.vm.launch()
283
284    def tearDown(self):
285        self.vm.shutdown()
286
287    def set_io_throttle(self, device, params):
288        params["device"] = device
289        result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
290        self.assert_qmp(result, 'return', {})
291
292    def verify_name(self, device, name):
293        result = self.vm.qmp("query-block")
294        for r in result["return"]:
295            if r["device"] == device:
296                info = r["inserted"]
297                if name:
298                    self.assertEqual(info["group"], name)
299                else:
300                    self.assertFalse('group' in info)
301                return
302
303        raise Exception("No group information found for '%s'" % device)
304
305    def test_group_naming(self):
306        params = {"bps": 0,
307                  "bps_rd": 0,
308                  "bps_wr": 0,
309                  "iops": 0,
310                  "iops_rd": 0,
311                  "iops_wr": 0}
312
313        # Check the drives added using the command line.
314        # The default throttling group name is the device name.
315        for i in range(self.max_drives):
316            devname = "drive%d" % i
317            self.verify_name(devname, devname)
318
319        # Clear throttling settings => the group name is gone.
320        for i in range(self.max_drives):
321            devname = "drive%d" % i
322            self.set_io_throttle(devname, params)
323            self.verify_name(devname, None)
324
325        # Set throttling settings using block_set_io_throttle and
326        # check the default group names.
327        params["iops"] = 10
328        for i in range(self.max_drives):
329            devname = "drive%d" % i
330            self.set_io_throttle(devname, params)
331            self.verify_name(devname, devname)
332
333        # Set a custom group name for each device
334        for i in range(3):
335            devname = "drive%d" % i
336            groupname = "group%d" % i
337            params['group'] = groupname
338            self.set_io_throttle(devname, params)
339            self.verify_name(devname, groupname)
340
341        # Put drive0 in group1 and check that all other devices remain
342        # unchanged
343        params['group'] = 'group1'
344        self.set_io_throttle('drive0', params)
345        self.verify_name('drive0', 'group1')
346        for i in range(1, self.max_drives):
347            devname = "drive%d" % i
348            groupname = "group%d" % i
349            self.verify_name(devname, groupname)
350
351        # Put drive0 in group2 and check that all other devices remain
352        # unchanged
353        params['group'] = 'group2'
354        self.set_io_throttle('drive0', params)
355        self.verify_name('drive0', 'group2')
356        for i in range(1, self.max_drives):
357            devname = "drive%d" % i
358            groupname = "group%d" % i
359            self.verify_name(devname, groupname)
360
361        # Clear throttling settings from drive0 check that all other
362        # devices remain unchanged
363        params["iops"] = 0
364        self.set_io_throttle('drive0', params)
365        self.verify_name('drive0', None)
366        for i in range(1, self.max_drives):
367            devname = "drive%d" % i
368            groupname = "group%d" % i
369            self.verify_name(devname, groupname)
370
371class ThrottleTestRemovableMedia(iotests.QMPTestCase):
372    def setUp(self):
373        self.vm = iotests.VM()
374        self.vm.add_device("{},id=virtio-scsi".format('virtio-scsi'))
375        self.vm.launch()
376
377    def tearDown(self):
378        self.vm.shutdown()
379
380    def test_removable_media(self):
381        # Add a couple of dummy nodes named cd0 and cd1
382        result = self.vm.qmp("blockdev-add", driver="null-co",
383                             read_zeroes=True, node_name="cd0")
384        self.assert_qmp(result, 'return', {})
385        result = self.vm.qmp("blockdev-add", driver="null-co",
386                             read_zeroes=True, node_name="cd1")
387        self.assert_qmp(result, 'return', {})
388
389        # Attach a CD drive with cd0 inserted
390        result = self.vm.qmp("device_add", driver="scsi-cd",
391                             id="dev0", drive="cd0")
392        self.assert_qmp(result, 'return', {})
393
394        # Set I/O limits
395        args = { "id": "dev0", "iops": 100, "iops_rd": 0, "iops_wr": 0,
396                                "bps":  50,  "bps_rd": 0,  "bps_wr": 0 }
397        result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **args)
398        self.assert_qmp(result, 'return', {})
399
400        # Check that the I/O limits have been set
401        result = self.vm.qmp("query-block")
402        self.assert_qmp(result, 'return[0]/inserted/iops', 100)
403        self.assert_qmp(result, 'return[0]/inserted/bps',   50)
404
405        # Now eject cd0 and insert cd1
406        result = self.vm.qmp("blockdev-open-tray", id='dev0')
407        self.assert_qmp(result, 'return', {})
408        result = self.vm.qmp("blockdev-remove-medium", id='dev0')
409        self.assert_qmp(result, 'return', {})
410        result = self.vm.qmp("blockdev-insert-medium", id='dev0', node_name='cd1')
411        self.assert_qmp(result, 'return', {})
412
413        # Check that the I/O limits are still the same
414        result = self.vm.qmp("query-block")
415        self.assert_qmp(result, 'return[0]/inserted/iops', 100)
416        self.assert_qmp(result, 'return[0]/inserted/bps',   50)
417
418        # Eject cd1
419        result = self.vm.qmp("blockdev-remove-medium", id='dev0')
420        self.assert_qmp(result, 'return', {})
421
422        # Check that we can't set limits if the device has no medium
423        result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **args)
424        self.assert_qmp(result, 'error/class', 'GenericError')
425
426        # Remove the CD drive
427        result = self.vm.qmp("device_del", id='dev0')
428        self.assert_qmp(result, 'return', {})
429
430
431if __name__ == '__main__':
432    if 'null-co' not in iotests.supported_formats():
433        iotests.notrun('null-co driver support missing')
434    iotests.main(supported_fmts=["raw"])
435