tests/qemu-iotests/093

   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
  22 import iotests
  23
  24 nsec_per_sec = 1000000000
  25
  26 class 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, "file.read-zeroes=on")
  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         # Allow remaining requests to finish.  We submitted twice as many to
 137         # ensure the throttle limit is reached.
 138         self.vm.qtest("clock_step %d" % ns)
 139
 140     # Connect N drives to a VM and test I/O in all of them
 141     def test_all(self):
 142         params = {"bps": 4096,
 143                   "bps_rd": 4096,
 144                   "bps_wr": 4096,
 145                   "iops": 10,
 146                   "iops_rd": 10,
 147                   "iops_wr": 10,
 148                  }
 149         # Repeat the test with different numbers of drives
 150         for ndrives in range(1, self.max_drives + 1):
 151             # Pick each out of all possible params and test
 152             for tk in params:
 153                 limits = dict([(k, 0) for k in params])
 154                 limits[tk] = params[tk] * ndrives
 155                 self.configure_throttle(ndrives, limits)
 156                 self.do_test_throttle(ndrives, 5, limits)
 157
 158     # Connect N drives to a VM and test I/O in just one of them a time
 159     def test_one(self):
 160         params = {"bps": 4096,
 161                   "bps_rd": 4096,
 162                   "bps_wr": 4096,
 163                   "iops": 10,
 164                   "iops_rd": 10,
 165                   "iops_wr": 10,
 166                  }
 167         # Repeat the test for each one of the drives
 168         for drive in range(0, self.max_drives):
 169             # Pick each out of all possible params and test
 170             for tk in params:
 171                 limits = dict([(k, 0) for k in params])
 172                 limits[tk] = params[tk] * self.max_drives
 173                 self.configure_throttle(self.max_drives, limits)
 174                 self.do_test_throttle(1, 5, limits, drive)
 175
 176     def test_burst(self):
 177         params = {"bps": 4096,
 178                   "bps_rd": 4096,
 179                   "bps_wr": 4096,
 180                   "iops": 10,
 181                   "iops_rd": 10,
 182                   "iops_wr": 10,
 183                  }
 184         ndrives = 1
 185         # Pick each out of all possible params and test
 186         for tk in params:
 187             rate = params[tk] * ndrives
 188             burst_rate = rate * 7
 189             burst_length = 4
 190
 191             # Configure the throttling settings
 192             settings = dict([(k, 0) for k in params])
 193             settings[tk] = rate
 194             settings['%s_max' % tk] = burst_rate
 195             settings['%s_max_length' % tk] = burst_length
 196             self.configure_throttle(ndrives, settings)
 197
 198             # Wait for the bucket to empty so we can do bursts
 199             wait_ns = nsec_per_sec * burst_length * burst_rate // rate
 200             self.vm.qtest("clock_step %d" % wait_ns)
 201
 202             # Test I/O at the max burst rate
 203             limits = dict([(k, 0) for k in params])
 204             limits[tk] = burst_rate
 205             self.do_test_throttle(ndrives, burst_length, limits)
 206
 207             # Now test I/O at the normal rate
 208             limits[tk] = rate
 209             self.do_test_throttle(ndrives, 5, limits)
 210
 211     # Test that removing a drive from a throttle group should not
 212     # affect the remaining members of the group.
 213     # https://bugzilla.redhat.com/show_bug.cgi?id=1535914
 214     def test_remove_group_member(self):
 215         # Create a throttle group with two drives
 216         # and set a 4 KB/s read limit.
 217         params = {"bps": 0,
 218                   "bps_rd": 4096,
 219                   "bps_wr": 0,
 220                   "iops": 0,
 221                   "iops_rd": 0,
 222                   "iops_wr": 0 }
 223         self.configure_throttle(2, params)
 224
 225         # Read 4KB from drive0. This is performed immediately.
 226         self.vm.hmp_qemu_io("drive0", "aio_read 0 4096")
 227
 228         # Read 2KB. The I/O limit has been exceeded so this
 229         # request is throttled and a timer is set to wake it up.
 230         self.vm.hmp_qemu_io("drive0", "aio_read 0 2048")
 231
 232         # Read 2KB again. We're still over the I/O limit so this is
 233         # request is also throttled, but no new timer is set since
 234         # there's already one.
 235         self.vm.hmp_qemu_io("drive0", "aio_read 0 2048")
 236
 237         # Read from drive1. This request is also throttled, and no
 238         # timer is set in drive1 because there's already one in
 239         # drive0.
 240         self.vm.hmp_qemu_io("drive1", "aio_read 0 4096")
 241
 242         # At this point only the first 4KB have been read from drive0.
 243         # The other requests are throttled.
 244         self.assertEqual(self.blockstats('drive0')[0], 4096)
 245         self.assertEqual(self.blockstats('drive1')[0], 0)
 246
 247         # Remove drive0 from the throttle group and disable its I/O limits.
 248         # drive1 remains in the group with a throttled request.
 249         params['bps_rd'] = 0
 250         params['device'] = 'drive0'
 251         result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
 252         self.assert_qmp(result, 'return', {})
 253
 254         # Removing the I/O limits from drive0 drains its two pending requests.
 255         # The read request in drive1 is still throttled.
 256         self.assertEqual(self.blockstats('drive0')[0], 8192)
 257         self.assertEqual(self.blockstats('drive1')[0], 0)
 258
 259         # Advance the clock 5 seconds. This completes the request in drive1
 260         self.vm.qtest("clock_step %d" % (5 * nsec_per_sec))
 261
 262         # Now all requests have been processed.
 263         self.assertEqual(self.blockstats('drive0')[0], 8192)
 264         self.assertEqual(self.blockstats('drive1')[0], 4096)
 265
 266 class ThrottleTestCoroutine(ThrottleTestCase):
 267     test_img = "null-co://"
 268
 269 class ThrottleTestGroupNames(iotests.QMPTestCase):
 270     test_img = "null-aio://"
 271     max_drives = 3
 272
 273     def setUp(self):
 274         self.vm = iotests.VM()
 275         for i in range(0, self.max_drives):
 276             self.vm.add_drive(self.test_img,
 277                               "throttling.iops-total=100,file.read-zeroes=on")
 278         self.vm.launch()
 279
 280     def tearDown(self):
 281         self.vm.shutdown()
 282
 283     def set_io_throttle(self, device, params):
 284         params["device"] = device
 285         result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **params)
 286         self.assert_qmp(result, 'return', {})
 287
 288     def verify_name(self, device, name):
 289         result = self.vm.qmp("query-block")
 290         for r in result["return"]:
 291             if r["device"] == device:
 292                 info = r["inserted"]
 293                 if name:
 294                     self.assertEqual(info["group"], name)
 295                 else:
 296                     self.assertFalse('group' in info)
 297                 return
 298
 299         raise Exception("No group information found for '%s'" % device)
 300
 301     def test_group_naming(self):
 302         params = {"bps": 0,
 303                   "bps_rd": 0,
 304                   "bps_wr": 0,
 305                   "iops": 0,
 306                   "iops_rd": 0,
 307                   "iops_wr": 0}
 308
 309         # Check the drives added using the command line.
 310         # The default throttling group name is the device name.
 311         for i in range(self.max_drives):
 312             devname = "drive%d" % i
 313             self.verify_name(devname, devname)
 314
 315         # Clear throttling settings => the group name is gone.
 316         for i in range(self.max_drives):
 317             devname = "drive%d" % i
 318             self.set_io_throttle(devname, params)
 319             self.verify_name(devname, None)
 320
 321         # Set throttling settings using block_set_io_throttle and
 322         # check the default group names.
 323         params["iops"] = 10
 324         for i in range(self.max_drives):
 325             devname = "drive%d" % i
 326             self.set_io_throttle(devname, params)
 327             self.verify_name(devname, devname)
 328
 329         # Set a custom group name for each device
 330         for i in range(3):
 331             devname = "drive%d" % i
 332             groupname = "group%d" % i
 333             params['group'] = groupname
 334             self.set_io_throttle(devname, params)
 335             self.verify_name(devname, groupname)
 336
 337         # Put drive0 in group1 and check that all other devices remain
 338         # unchanged
 339         params['group'] = 'group1'
 340         self.set_io_throttle('drive0', params)
 341         self.verify_name('drive0', 'group1')
 342         for i in range(1, self.max_drives):
 343             devname = "drive%d" % i
 344             groupname = "group%d" % i
 345             self.verify_name(devname, groupname)
 346
 347         # Put drive0 in group2 and check that all other devices remain
 348         # unchanged
 349         params['group'] = 'group2'
 350         self.set_io_throttle('drive0', params)
 351         self.verify_name('drive0', 'group2')
 352         for i in range(1, self.max_drives):
 353             devname = "drive%d" % i
 354             groupname = "group%d" % i
 355             self.verify_name(devname, groupname)
 356
 357         # Clear throttling settings from drive0 check that all other
 358         # devices remain unchanged
 359         params["iops"] = 0
 360         self.set_io_throttle('drive0', params)
 361         self.verify_name('drive0', None)
 362         for i in range(1, self.max_drives):
 363             devname = "drive%d" % i
 364             groupname = "group%d" % i
 365             self.verify_name(devname, groupname)
 366
 367 class ThrottleTestRemovableMedia(iotests.QMPTestCase):
 368     def setUp(self):
 369         self.vm = iotests.VM()
 370         self.vm.add_device("{},id=virtio-scsi".format(
 371             iotests.get_virtio_scsi_device()))
 372         self.vm.launch()
 373
 374     def tearDown(self):
 375         self.vm.shutdown()
 376
 377     def test_removable_media(self):
 378         # Add a couple of dummy nodes named cd0 and cd1
 379         result = self.vm.qmp("blockdev-add", driver="null-aio",
 380                              read_zeroes=True, node_name="cd0")
 381         self.assert_qmp(result, 'return', {})
 382         result = self.vm.qmp("blockdev-add", driver="null-aio",
 383                              read_zeroes=True, node_name="cd1")
 384         self.assert_qmp(result, 'return', {})
 385
 386         # Attach a CD drive with cd0 inserted
 387         result = self.vm.qmp("device_add", driver="scsi-cd",
 388                              id="dev0", drive="cd0")
 389         self.assert_qmp(result, 'return', {})
 390
 391         # Set I/O limits
 392         args = { "id": "dev0", "iops": 100, "iops_rd": 0, "iops_wr": 0,
 393                                 "bps":  50,  "bps_rd": 0,  "bps_wr": 0 }
 394         result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **args)
 395         self.assert_qmp(result, 'return', {})
 396
 397         # Check that the I/O limits have been set
 398         result = self.vm.qmp("query-block")
 399         self.assert_qmp(result, 'return[0]/inserted/iops', 100)
 400         self.assert_qmp(result, 'return[0]/inserted/bps',   50)
 401
 402         # Now eject cd0 and insert cd1
 403         result = self.vm.qmp("blockdev-open-tray", id='dev0')
 404         self.assert_qmp(result, 'return', {})
 405         result = self.vm.qmp("blockdev-remove-medium", id='dev0')
 406         self.assert_qmp(result, 'return', {})
 407         result = self.vm.qmp("blockdev-insert-medium", id='dev0', node_name='cd1')
 408         self.assert_qmp(result, 'return', {})
 409
 410         # Check that the I/O limits are still the same
 411         result = self.vm.qmp("query-block")
 412         self.assert_qmp(result, 'return[0]/inserted/iops', 100)
 413         self.assert_qmp(result, 'return[0]/inserted/bps',   50)
 414
 415         # Eject cd1
 416         result = self.vm.qmp("blockdev-remove-medium", id='dev0')
 417         self.assert_qmp(result, 'return', {})
 418
 419         # Check that we can't set limits if the device has no medium
 420         result = self.vm.qmp("block_set_io_throttle", conv_keys=False, **args)
 421         self.assert_qmp(result, 'error/class', 'GenericError')
 422
 423         # Remove the CD drive
 424         result = self.vm.qmp("device_del", id='dev0')
 425         self.assert_qmp(result, 'return', {})
 426
 427
 428 if __name__ == '__main__':
 429     iotests.main(supported_fmts=["raw"])