xref: /openbmc/qemu/tests/qemu-iotests/093 (revision 2a886794)
1#!/usr/bin/env python
2#
3# Tests for IO throttling
4#
5# Copyright (C) 2015 Red Hat, Inc.
6# Copyright (C) 2015-2016 Igalia, S.L.
7#
8# This program is free software; you can redistribute it and/or modify
9# it under the terms of the GNU General Public License as published by
10# the Free Software Foundation; either version 2 of the License, or
11# (at your option) any later version.
12#
13# This program is distributed in the hope that it will be useful,
14# but WITHOUT ANY WARRANTY; without even the implied warranty of
15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16# GNU General Public License for more details.
17#
18# You should have received a copy of the GNU General Public License
19# along with this program.  If not, see <http://www.gnu.org/licenses/>.
20#
21
22import iotests
23
24nsec_per_sec = 1000000000
25
26class ThrottleTestCase(iotests.QMPTestCase):
27    test_driver = "null-aio"
28    max_drives = 3
29
30    def blockstats(self, device):
31        result = self.vm.qmp("query-blockstats")
32        for r in result['return']:
33            if r['device'] == device:
34                stat = r['stats']
35                return stat['rd_bytes'], stat['rd_operations'], stat['wr_bytes'], stat['wr_operations']
36        raise Exception("Device not found for blockstats: %s" % device)
37
38    def required_drivers(self):
39        return [self.test_driver]
40
41    @iotests.skip_if_unsupported(required_drivers)
42    def setUp(self):
43        self.vm = iotests.VM()
44        for i in range(0, self.max_drives):
45            self.vm.add_drive(self.test_driver + "://", "file.read-zeroes=on")
46        self.vm.launch()
47
48    def tearDown(self):
49        self.vm.shutdown()
50
51    def configure_throttle(self, ndrives, params):
52        params['group'] = 'test'
53
54        # Set the I/O throttling parameters to all drives
55        for i in range(0, ndrives):
56            params['device'] = 'drive%d' % i
57            result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
58            self.assert_qmp(result, 'return', {})
59
60    def do_test_throttle(self, ndrives, seconds, params, first_drive = 0):
61        def check_limit(limit, num):
62            # IO throttling algorithm is discrete, allow 10% error so the test
63            # is more robust
64            return limit == 0 or \
65                   (num < seconds * limit * 1.1 / ndrives
66                   and num > seconds * limit * 0.9 / ndrives)
67
68        # Set vm clock to a known value
69        ns = seconds * nsec_per_sec
70        self.vm.qtest("clock_step %d" % ns)
71
72        # Submit enough requests so the throttling mechanism kicks
73        # in. The throttled requests won't be executed until we
74        # advance the virtual clock.
75        rq_size = 512
76        rd_nr = max(params['bps'] // rq_size // 2,
77                    params['bps_rd'] // rq_size,
78                    params['iops'] // 2,
79                    params['iops_rd'])
80        rd_nr *= seconds * 2
81        rd_nr //= ndrives
82        wr_nr = max(params['bps'] // rq_size // 2,
83                    params['bps_wr'] // rq_size,
84                    params['iops'] // 2,
85                    params['iops_wr'])
86        wr_nr *= seconds * 2
87        wr_nr //= ndrives
88
89        # Send I/O requests to all drives
90        for i in range(rd_nr):
91            for drive in range(0, ndrives):
92                idx = first_drive + drive
93                self.vm.hmp_qemu_io("drive%d" % idx, "aio_read %d %d" %
94                                    (i * rq_size, rq_size))
95
96        for i in range(wr_nr):
97            for drive in range(0, ndrives):
98                idx = first_drive + drive
99                self.vm.hmp_qemu_io("drive%d" % idx, "aio_write %d %d" %
100                                    (i * rq_size, rq_size))
101
102        # We'll store the I/O stats for each drive in these arrays
103        start_rd_bytes = [0] * ndrives
104        start_rd_iops  = [0] * ndrives
105        start_wr_bytes = [0] * ndrives
106        start_wr_iops  = [0] * ndrives
107        end_rd_bytes   = [0] * ndrives
108        end_rd_iops    = [0] * ndrives
109        end_wr_bytes   = [0] * ndrives
110        end_wr_iops    = [0] * ndrives
111
112        # Read the stats before advancing the clock
113        for i in range(0, ndrives):
114            idx = first_drive + i
115            start_rd_bytes[i], start_rd_iops[i], start_wr_bytes[i], \
116                start_wr_iops[i] = self.blockstats('drive%d' % idx)
117
118        self.vm.qtest("clock_step %d" % ns)
119
120        # Read the stats after advancing the clock
121        for i in range(0, ndrives):
122            idx = first_drive + i
123            end_rd_bytes[i], end_rd_iops[i], end_wr_bytes[i], \
124                end_wr_iops[i] = self.blockstats('drive%d' % idx)
125
126        # Check that the I/O is within the limits and evenly distributed
127        for i in range(0, ndrives):
128            rd_bytes = end_rd_bytes[i] - start_rd_bytes[i]
129            rd_iops = end_rd_iops[i] - start_rd_iops[i]
130            wr_bytes = end_wr_bytes[i] - start_wr_bytes[i]
131            wr_iops = end_wr_iops[i] - start_wr_iops[i]
132
133            self.assertTrue(check_limit(params['bps'], rd_bytes + wr_bytes))
134            self.assertTrue(check_limit(params['bps_rd'], rd_bytes))
135            self.assertTrue(check_limit(params['bps_wr'], wr_bytes))
136            self.assertTrue(check_limit(params['iops'], rd_iops + wr_iops))
137            self.assertTrue(check_limit(params['iops_rd'], rd_iops))
138            self.assertTrue(check_limit(params['iops_wr'], wr_iops))
139
140        # Allow remaining requests to finish.  We submitted twice as many to
141        # ensure the throttle limit is reached.
142        self.vm.qtest("clock_step %d" % ns)
143
144    # Connect N drives to a VM and test I/O in all of them
145    def test_all(self):
146        params = {"bps": 4096,
147                  "bps_rd": 4096,
148                  "bps_wr": 4096,
149                  "iops": 10,
150                  "iops_rd": 10,
151                  "iops_wr": 10,
152                 }
153        # Repeat the test with different numbers of drives
154        for ndrives in range(1, self.max_drives + 1):
155            # Pick each out of all possible params and test
156            for tk in params:
157                limits = dict([(k, 0) for k in params])
158                limits[tk] = params[tk] * ndrives
159                self.configure_throttle(ndrives, limits)
160                self.do_test_throttle(ndrives, 5, limits)
161
162    # Connect N drives to a VM and test I/O in just one of them a time
163    def test_one(self):
164        params = {"bps": 4096,
165                  "bps_rd": 4096,
166                  "bps_wr": 4096,
167                  "iops": 10,
168                  "iops_rd": 10,
169                  "iops_wr": 10,
170                 }
171        # Repeat the test for each one of the drives
172        for drive in range(0, self.max_drives):
173            # Pick each out of all possible params and test
174            for tk in params:
175                limits = dict([(k, 0) for k in params])
176                limits[tk] = params[tk] * self.max_drives
177                self.configure_throttle(self.max_drives, limits)
178                self.do_test_throttle(1, 5, limits, drive)
179
180    def test_burst(self):
181        params = {"bps": 4096,
182                  "bps_rd": 4096,
183                  "bps_wr": 4096,
184                  "iops": 10,
185                  "iops_rd": 10,
186                  "iops_wr": 10,
187                 }
188        ndrives = 1
189        # Pick each out of all possible params and test
190        for tk in params:
191            rate = params[tk] * ndrives
192            burst_rate = rate * 7
193            burst_length = 4
194
195            # Configure the throttling settings
196            settings = dict([(k, 0) for k in params])
197            settings[tk] = rate
198            settings['%s_max' % tk] = burst_rate
199            settings['%s_max_length' % tk] = burst_length
200            self.configure_throttle(ndrives, settings)
201
202            # Wait for the bucket to empty so we can do bursts
203            wait_ns = nsec_per_sec * burst_length * burst_rate // rate
204            self.vm.qtest("clock_step %d" % wait_ns)
205
206            # Test I/O at the max burst rate
207            limits = dict([(k, 0) for k in params])
208            limits[tk] = burst_rate
209            self.do_test_throttle(ndrives, burst_length, limits)
210
211            # Now test I/O at the normal rate
212            limits[tk] = rate
213            self.do_test_throttle(ndrives, 5, limits)
214
215    # Test that removing a drive from a throttle group should not
216    # affect the remaining members of the group.
217    # https://bugzilla.redhat.com/show_bug.cgi?id=1535914
218    def test_remove_group_member(self):
219        # Create a throttle group with two drives
220        # and set a 4 KB/s read limit.
221        params = {"bps": 0,
222                  "bps_rd": 4096,
223                  "bps_wr": 0,
224                  "iops": 0,
225                  "iops_rd": 0,
226                  "iops_wr": 0 }
227        self.configure_throttle(2, params)
228
229        # Read 4KB from drive0. This is performed immediately.
230        self.vm.hmp_qemu_io("drive0", "aio_read 0 4096")
231
232        # Read 2KB. The I/O limit has been exceeded so this
233        # request is throttled and a timer is set to wake it up.
234        self.vm.hmp_qemu_io("drive0", "aio_read 0 2048")
235
236        # Read 2KB again. We're still over the I/O limit so this is
237        # request is also throttled, but no new timer is set since
238        # there's already one.
239        self.vm.hmp_qemu_io("drive0", "aio_read 0 2048")
240
241        # Read from drive1. This request is also throttled, and no
242        # timer is set in drive1 because there's already one in
243        # drive0.
244        self.vm.hmp_qemu_io("drive1", "aio_read 0 4096")
245
246        # At this point only the first 4KB have been read from drive0.
247        # The other requests are throttled.
248        self.assertEqual(self.blockstats('drive0')[0], 4096)
249        self.assertEqual(self.blockstats('drive1')[0], 0)
250
251        # Remove drive0 from the throttle group and disable its I/O limits.
252        # drive1 remains in the group with a throttled request.
253        params['bps_rd'] = 0
254        params['device'] = 'drive0'
255        result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
256        self.assert_qmp(result, 'return', {})
257
258        # Removing the I/O limits from drive0 drains its two pending requests.
259        # The read request in drive1 is still throttled.
260        self.assertEqual(self.blockstats('drive0')[0], 8192)
261        self.assertEqual(self.blockstats('drive1')[0], 0)
262
263        # Advance the clock 5 seconds. This completes the request in drive1
264        self.vm.qtest("clock_step %d" % (5 * nsec_per_sec))
265
266        # Now all requests have been processed.
267        self.assertEqual(self.blockstats('drive0')[0], 8192)
268        self.assertEqual(self.blockstats('drive1')[0], 4096)
269
270class ThrottleTestCoroutine(ThrottleTestCase):
271    test_driver = "null-co"
272
273class ThrottleTestGroupNames(iotests.QMPTestCase):
274    max_drives = 3
275
276    def setUp(self):
277        self.vm = iotests.VM()
278        for i in range(0, self.max_drives):
279            self.vm.add_drive("null-co://",
280                              "throttling.iops-total=100,file.read-zeroes=on")
281        self.vm.launch()
282
283    def tearDown(self):
284        self.vm.shutdown()
285
286    def set_io_throttle(self, device, params):
287        params["device"] = device
288        result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
289        self.assert_qmp(result, 'return', {})
290
291    def verify_name(self, device, name):
292        result = self.vm.qmp("query-block")
293        for r in result["return"]:
294            if r["device"] == device:
295                info = r["inserted"]
296                if name:
297                    self.assertEqual(info["group"], name)
298                else:
299                    self.assertFalse('group' in info)
300                return
301
302        raise Exception("No group information found for '%s'" % device)
303
304    def test_group_naming(self):
305        params = {"bps": 0,
306                  "bps_rd": 0,
307                  "bps_wr": 0,
308                  "iops": 0,
309                  "iops_rd": 0,
310                  "iops_wr": 0}
311
312        # Check the drives added using the command line.
313        # The default throttling group name is the device name.
314        for i in range(self.max_drives):
315            devname = "drive%d" % i
316            self.verify_name(devname, devname)
317
318        # Clear throttling settings => the group name is gone.
319        for i in range(self.max_drives):
320            devname = "drive%d" % i
321            self.set_io_throttle(devname, params)
322            self.verify_name(devname, None)
323
324        # Set throttling settings using block_set_io_throttle and
325        # check the default group names.
326        params["iops"] = 10
327        for i in range(self.max_drives):
328            devname = "drive%d" % i
329            self.set_io_throttle(devname, params)
330            self.verify_name(devname, devname)
331
332        # Set a custom group name for each device
333        for i in range(3):
334            devname = "drive%d" % i
335            groupname = "group%d" % i
336            params['group'] = groupname
337            self.set_io_throttle(devname, params)
338            self.verify_name(devname, groupname)
339
340        # Put drive0 in group1 and check that all other devices remain
341        # unchanged
342        params['group'] = 'group1'
343        self.set_io_throttle('drive0', params)
344        self.verify_name('drive0', 'group1')
345        for i in range(1, self.max_drives):
346            devname = "drive%d" % i
347            groupname = "group%d" % i
348            self.verify_name(devname, groupname)
349
350        # Put drive0 in group2 and check that all other devices remain
351        # unchanged
352        params['group'] = 'group2'
353        self.set_io_throttle('drive0', params)
354        self.verify_name('drive0', 'group2')
355        for i in range(1, self.max_drives):
356            devname = "drive%d" % i
357            groupname = "group%d" % i
358            self.verify_name(devname, groupname)
359
360        # Clear throttling settings from drive0 check that all other
361        # devices remain unchanged
362        params["iops"] = 0
363        self.set_io_throttle('drive0', params)
364        self.verify_name('drive0', None)
365        for i in range(1, self.max_drives):
366            devname = "drive%d" % i
367            groupname = "group%d" % i
368            self.verify_name(devname, groupname)
369
370class ThrottleTestRemovableMedia(iotests.QMPTestCase):
371    def setUp(self):
372        self.vm = iotests.VM()
373        self.vm.add_device("{},id=virtio-scsi".format(
374            iotests.get_virtio_scsi_device()))
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