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