xref: /openbmc/qemu/tests/qemu-iotests/093 (revision e4370165)
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_img = "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 setUp(self):
39        self.vm = iotests.VM()
40        for i in range(0, self.max_drives):
41            self.vm.add_drive(self.test_img)
42        self.vm.launch()
43
44    def tearDown(self):
45        self.vm.shutdown()
46
47    def configure_throttle(self, ndrives, params):
48        params['group'] = 'test'
49
50        # Set the I/O throttling parameters to all drives
51        for i in range(0, ndrives):
52            params['device'] = 'drive%d' % i
53            result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
54            self.assert_qmp(result, 'return', {})
55
56    def do_test_throttle(self, ndrives, seconds, params, first_drive = 0):
57        def check_limit(limit, num):
58            # IO throttling algorithm is discrete, allow 10% error so the test
59            # is more robust
60            return limit == 0 or \
61                   (num < seconds * limit * 1.1 / ndrives
62                   and num > seconds * limit * 0.9 / ndrives)
63
64        # Set vm clock to a known value
65        ns = seconds * nsec_per_sec
66        self.vm.qtest("clock_step %d" % ns)
67
68        # Submit enough requests so the throttling mechanism kicks
69        # in. The throttled requests won't be executed until we
70        # advance the virtual clock.
71        rq_size = 512
72        rd_nr = max(params['bps'] / rq_size / 2,
73                    params['bps_rd'] / rq_size,
74                    params['iops'] / 2,
75                    params['iops_rd'])
76        rd_nr *= seconds * 2
77        rd_nr /= ndrives
78        wr_nr = max(params['bps'] / rq_size / 2,
79                    params['bps_wr'] / rq_size,
80                    params['iops'] / 2,
81                    params['iops_wr'])
82        wr_nr *= seconds * 2
83        wr_nr /= ndrives
84
85        # Send I/O requests to all drives
86        for i in range(rd_nr):
87            for drive in range(0, ndrives):
88                idx = first_drive + drive
89                self.vm.hmp_qemu_io("drive%d" % idx, "aio_read %d %d" %
90                                    (i * rq_size, rq_size))
91
92        for i in range(wr_nr):
93            for drive in range(0, ndrives):
94                idx = first_drive + drive
95                self.vm.hmp_qemu_io("drive%d" % idx, "aio_write %d %d" %
96                                    (i * rq_size, rq_size))
97
98        # We'll store the I/O stats for each drive in these arrays
99        start_rd_bytes = [0] * ndrives
100        start_rd_iops  = [0] * ndrives
101        start_wr_bytes = [0] * ndrives
102        start_wr_iops  = [0] * ndrives
103        end_rd_bytes   = [0] * ndrives
104        end_rd_iops    = [0] * ndrives
105        end_wr_bytes   = [0] * ndrives
106        end_wr_iops    = [0] * ndrives
107
108        # Read the stats before advancing the clock
109        for i in range(0, ndrives):
110            idx = first_drive + i
111            start_rd_bytes[i], start_rd_iops[i], start_wr_bytes[i], \
112                start_wr_iops[i] = self.blockstats('drive%d' % idx)
113
114        self.vm.qtest("clock_step %d" % ns)
115
116        # Read the stats after advancing the clock
117        for i in range(0, ndrives):
118            idx = first_drive + i
119            end_rd_bytes[i], end_rd_iops[i], end_wr_bytes[i], \
120                end_wr_iops[i] = self.blockstats('drive%d' % idx)
121
122        # Check that the I/O is within the limits and evenly distributed
123        for i in range(0, ndrives):
124            rd_bytes = end_rd_bytes[i] - start_rd_bytes[i]
125            rd_iops = end_rd_iops[i] - start_rd_iops[i]
126            wr_bytes = end_wr_bytes[i] - start_wr_bytes[i]
127            wr_iops = end_wr_iops[i] - start_wr_iops[i]
128
129            self.assertTrue(check_limit(params['bps'], rd_bytes + wr_bytes))
130            self.assertTrue(check_limit(params['bps_rd'], rd_bytes))
131            self.assertTrue(check_limit(params['bps_wr'], wr_bytes))
132            self.assertTrue(check_limit(params['iops'], rd_iops + wr_iops))
133            self.assertTrue(check_limit(params['iops_rd'], rd_iops))
134            self.assertTrue(check_limit(params['iops_wr'], wr_iops))
135
136    # Connect N drives to a VM and test I/O in all of them
137    def test_all(self):
138        params = {"bps": 4096,
139                  "bps_rd": 4096,
140                  "bps_wr": 4096,
141                  "iops": 10,
142                  "iops_rd": 10,
143                  "iops_wr": 10,
144                 }
145        # Repeat the test with different numbers of drives
146        for ndrives in range(1, self.max_drives + 1):
147            # Pick each out of all possible params and test
148            for tk in params:
149                limits = dict([(k, 0) for k in params])
150                limits[tk] = params[tk] * ndrives
151                self.configure_throttle(ndrives, limits)
152                self.do_test_throttle(ndrives, 5, limits)
153
154    # Connect N drives to a VM and test I/O in just one of them a time
155    def test_one(self):
156        params = {"bps": 4096,
157                  "bps_rd": 4096,
158                  "bps_wr": 4096,
159                  "iops": 10,
160                  "iops_rd": 10,
161                  "iops_wr": 10,
162                 }
163        # Repeat the test for each one of the drives
164        for drive in range(0, self.max_drives):
165            # Pick each out of all possible params and test
166            for tk in params:
167                limits = dict([(k, 0) for k in params])
168                limits[tk] = params[tk] * self.max_drives
169                self.configure_throttle(self.max_drives, limits)
170                self.do_test_throttle(1, 5, limits, drive)
171
172    def test_burst(self):
173        params = {"bps": 4096,
174                  "bps_rd": 4096,
175                  "bps_wr": 4096,
176                  "iops": 10,
177                  "iops_rd": 10,
178                  "iops_wr": 10,
179                 }
180        ndrives = 1
181        # Pick each out of all possible params and test
182        for tk in params:
183            rate = params[tk] * ndrives
184            burst_rate = rate * 7
185            burst_length = 4
186
187            # Configure the throttling settings
188            settings = dict([(k, 0) for k in params])
189            settings[tk] = rate
190            settings['%s_max' % tk] = burst_rate
191            settings['%s_max_length' % tk] = burst_length
192            self.configure_throttle(ndrives, settings)
193
194            # Wait for the bucket to empty so we can do bursts
195            wait_ns = nsec_per_sec * burst_length * burst_rate / rate
196            self.vm.qtest("clock_step %d" % wait_ns)
197
198            # Test I/O at the max burst rate
199            limits = dict([(k, 0) for k in params])
200            limits[tk] = burst_rate
201            self.do_test_throttle(ndrives, burst_length, limits)
202
203            # Now test I/O at the normal rate
204            limits[tk] = rate
205            self.do_test_throttle(ndrives, 5, limits)
206
207class ThrottleTestCoroutine(ThrottleTestCase):
208    test_img = "null-co://"
209
210class ThrottleTestGroupNames(iotests.QMPTestCase):
211    test_img = "null-aio://"
212    max_drives = 3
213
214    def setUp(self):
215        self.vm = iotests.VM()
216        for i in range(0, self.max_drives):
217            self.vm.add_drive(self.test_img, "throttling.iops-total=100")
218        self.vm.launch()
219
220    def tearDown(self):
221        self.vm.shutdown()
222
223    def set_io_throttle(self, device, params):
224        params["device"] = device
225        result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
226        self.assert_qmp(result, 'return', {})
227
228    def verify_name(self, device, name):
229        result = self.vm.qmp("query-block")
230        for r in result["return"]:
231            if r["device"] == device:
232                info = r["inserted"]
233                if name:
234                    self.assertEqual(info["group"], name)
235                else:
236                    self.assertFalse(info.has_key('group'))
237                return
238
239        raise Exception("No group information found for '%s'" % device)
240
241    def test_group_naming(self):
242        params = {"bps": 0,
243                  "bps_rd": 0,
244                  "bps_wr": 0,
245                  "iops": 0,
246                  "iops_rd": 0,
247                  "iops_wr": 0}
248
249        # Check the drives added using the command line.
250        # The default throttling group name is the device name.
251        for i in range(self.max_drives):
252            devname = "drive%d" % i
253            self.verify_name(devname, devname)
254
255        # Clear throttling settings => the group name is gone.
256        for i in range(self.max_drives):
257            devname = "drive%d" % i
258            self.set_io_throttle(devname, params)
259            self.verify_name(devname, None)
260
261        # Set throttling settings using block_set_io_throttle and
262        # check the default group names.
263        params["iops"] = 10
264        for i in range(self.max_drives):
265            devname = "drive%d" % i
266            self.set_io_throttle(devname, params)
267            self.verify_name(devname, devname)
268
269        # Set a custom group name for each device
270        for i in range(3):
271            devname = "drive%d" % i
272            groupname = "group%d" % i
273            params['group'] = groupname
274            self.set_io_throttle(devname, params)
275            self.verify_name(devname, groupname)
276
277        # Put drive0 in group1 and check that all other devices remain
278        # unchanged
279        params['group'] = 'group1'
280        self.set_io_throttle('drive0', params)
281        self.verify_name('drive0', 'group1')
282        for i in range(1, self.max_drives):
283            devname = "drive%d" % i
284            groupname = "group%d" % i
285            self.verify_name(devname, groupname)
286
287        # Put drive0 in group2 and check that all other devices remain
288        # unchanged
289        params['group'] = 'group2'
290        self.set_io_throttle('drive0', params)
291        self.verify_name('drive0', 'group2')
292        for i in range(1, self.max_drives):
293            devname = "drive%d" % i
294            groupname = "group%d" % i
295            self.verify_name(devname, groupname)
296
297        # Clear throttling settings from drive0 check that all other
298        # devices remain unchanged
299        params["iops"] = 0
300        self.set_io_throttle('drive0', params)
301        self.verify_name('drive0', None)
302        for i in range(1, self.max_drives):
303            devname = "drive%d" % i
304            groupname = "group%d" % i
305            self.verify_name(devname, groupname)
306
307
308if __name__ == '__main__':
309    iotests.main(supported_fmts=["raw"])
310