On Wed, 01/28 11:22, Max Reitz wrote: > On 2015-01-27 at 21:28, Fam Zheng wrote: > >This case utilizes qemu-io command "aio_{read,write} -q" to verify the > >effectiveness of IO throttling options. > > > >It's implemented by driving the vm timer from qtest protocol, so the > >throttling timers are signaled with determinied time duration. Then we > >verify the completed IO requests are within 10% error of bps and iops > >limits. > > > >"null" protocol is used as the disk backend so that no actual disk IO is > >performed on host, this will make the blockstats much more > >deterministic. Both "null-aio" and "null-co" are covered, which is also > >a simple cross validation test for the driver code. > > > >Signed-off-by: Fam Zheng <f...@redhat.com> > >--- > > tests/qemu-iotests/093 | 120 > > +++++++++++++++++++++++++++++++++++++++++++++ > > tests/qemu-iotests/093.out | 5 ++ > > tests/qemu-iotests/group | 1 + > > 3 files changed, 126 insertions(+) > > create mode 100755 tests/qemu-iotests/093 > > create mode 100644 tests/qemu-iotests/093.out > > > >diff --git a/tests/qemu-iotests/093 b/tests/qemu-iotests/093 > >new file mode 100755 > >index 0000000..2866536 > >--- /dev/null > >+++ b/tests/qemu-iotests/093 > >@@ -0,0 +1,120 @@ > >+#!/usr/bin/env python > >+# > >+# Tests for IO throttling > >+# > >+# Copyright (C) 2015 Red Hat, Inc. > >+# > >+# This program is free software; you can redistribute it and/or modify > >+# it under the terms of the GNU General Public License as published by > >+# the Free Software Foundation; either version 2 of the License, or > >+# (at your option) any later version. > >+# > >+# This program is distributed in the hope that it will be useful, > >+# but WITHOUT ANY WARRANTY; without even the implied warranty of > >+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > >+# GNU General Public License for more details. > >+# > >+# You should have received a copy of the GNU General Public License > >+# along with this program. If not, see <http://www.gnu.org/licenses/>. > >+# > >+ > >+import iotests > >+ > >+class ThrottleTestCase(iotests.QMPTestCase): > >+ test_img = "null-aio://" > >+ > >+ def blockstats(self, device): > >+ result = self.vm.qmp("query-blockstats") > >+ for r in result['return']: > >+ if r['device'] == device: > >+ stat = r['stats'] > >+ return stat['rd_bytes'], stat['rd_operations'], > >stat['wr_bytes'], stat['wr_operations'] > >+ raise Exception("Device not found for blockstats: %s" % device) > >+ > >+ def setUp(self): > >+ self.vm = iotests.VM().add_drive(self.test_img) > >+ self.vm.launch() > >+ > >+ def tearDown(self): > >+ self.vm.shutdown() > >+ > >+ def do_test_throttle(self, seconds, params): > >+ def check_limit(limit, num): > >+ # IO throttling algorithm is discrete, allow 10% error so the > >test > >+ # is more robust > >+ return limit == 0 or \ > >+ (num < seconds * limit * 1.1 > >+ and num > seconds * limit * 0.9) > >+ > >+ nsec_per_sec = 1000000000 > >+ > >+ params['device'] = 'drive0' > >+ > >+ result = self.vm.qmp("block_set_io_throttle", conv_keys=False, > >**params) > >+ self.assert_qmp(result, 'return', {}) > >+ > >+ # Set vm clock to a known value > >+ ns = seconds * nsec_per_sec > >+ self.vm.qtest("clock_step %d" % ns) > >+ > >+ # Submit enough requests. They will drain bps_max and iops_max, but > >the > >+ # rest requests won't get executed until we advance the virtual > >clock > >+ # with qtest interface > >+ rq_size = 512 > >+ rd_nr = max(params['bps'] / rq_size / 2, > >+ params['bps_rd'] / rq_size, > >+ params['iops'] / 2, > >+ params['iops_rd']) + \ > >+ params['bps_max'] / rq_size / 2 + \ > >+ params['iops_max'] > > I guess the divisions by two are because those values represent read and > write operations combined. Shouldn't iops_max be divided by two, too, then? > > >+ rd_nr *= seconds * 2 > >+ wr_nr = max(params['bps'] / rq_size / 2, > >+ params['bps_wr'] / rq_size, > >+ params['iops'] / 2, > >+ params['iops_wr']) + \ > >+ params['bps_max'] / rq_size / 2 + \ > >+ params['iops_max'] > >+ wr_nr *= seconds * 2 > >+ for i in range(rd_nr): > >+ self.vm.hmp_qemu_io("drive0", "aio_read %d %d" % (i * rq_size, > >rq_size)) > >+ for i in range(wr_nr): > >+ self.vm.hmp_qemu_io("drive0", "aio_write %d %d" % (i * rq_size, > >rq_size)) > >+ > >+ start_rd_bytes, start_rd_iops, start_wr_bytes, start_wr_iops = > >self.blockstats('drive0') > >+ > >+ self.vm.qtest("clock_step %d" % ns) > >+ end_rd_bytes, end_rd_iops, end_wr_bytes, end_wr_iops = > >self.blockstats('drive0') > >+ > >+ rd_bytes = end_rd_bytes - start_rd_bytes > >+ rd_iops = end_rd_iops - start_rd_iops > >+ wr_bytes = end_wr_bytes - start_wr_bytes > >+ wr_iops = end_wr_iops - start_wr_iops > >+ > >+ self.assertTrue(check_limit(params['bps'], rd_bytes + wr_bytes)) > >+ self.assertTrue(check_limit(params['bps_rd'], rd_bytes)) > >+ self.assertTrue(check_limit(params['bps_wr'], wr_bytes)) > >+ self.assertTrue(check_limit(params['iops'], rd_iops + wr_iops)) > >+ self.assertTrue(check_limit(params['iops_rd'], rd_iops)) > >+ self.assertTrue(check_limit(params['iops_wr'], wr_iops)) > > Hm, you're not checking bps_max and iops_max here. Should you be?
I never really liked these two parameters, but now that you asked, probably yes (to this question and above). :) Fam > > Apart from these two (minor) things: Works for me! :-) > > Max > > >+ > >+ def test_all(self): > >+ params = {"bps": 4096, > >+ "bps_rd": 4096, > >+ "bps_wr": 4096, > >+ "bps_max": 4096, > >+ "iops": 10, > >+ "iops_rd": 10, > >+ "iops_wr": 10, > >+ "iops_max": 10, > >+ } > >+ # Pick each out of all possible params and test > >+ for tk in params: > >+ limits = dict([(k, 0) for k in params]) > >+ limits[tk] = params[tk] > >+ self.do_test_throttle(5, limits) > >+ > >+class ThrottleTestCoroutine(ThrottleTestCase): > >+ test_img = "null-co://" > >+ > >+if __name__ == '__main__': > >+ iotests.main(supported_fmts=["raw"]) > >diff --git a/tests/qemu-iotests/093.out b/tests/qemu-iotests/093.out > >new file mode 100644 > >index 0000000..fbc63e6 > >--- /dev/null > >+++ b/tests/qemu-iotests/093.out > >@@ -0,0 +1,5 @@ > >+.. > >+---------------------------------------------------------------------- > >+Ran 2 tests > >+ > >+OK > >diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group > >index f8bf354..0272c9a 100644 > >--- a/tests/qemu-iotests/group > >+++ b/tests/qemu-iotests/group > >@@ -99,6 +99,7 @@ > > 090 rw auto quick > > 091 rw auto > > 092 rw auto quick > >+093 auto > > 095 rw auto quick > > 097 rw auto backing > > 098 rw auto backing quick >