The Tuesday 11 Feb 2014 à 14:41:02 (+0800), 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 determined time duration. Then we
> verify the completed IO requests are within 110% of bps and iops limits.
>
> Signed-off-by: Fam Zheng <f...@redhat.com>
> ---
> tests/qemu-iotests/080 | 175
> +++++++++++++++++++++++++++++++++++++++++++++
> tests/qemu-iotests/080.out | 5 ++
> tests/qemu-iotests/group | 1 +
> 3 files changed, 181 insertions(+)
> create mode 100755 tests/qemu-iotests/080
> create mode 100644 tests/qemu-iotests/080.out
>
> diff --git a/tests/qemu-iotests/080 b/tests/qemu-iotests/080
> new file mode 100755
> index 0000000..9e2c762
> --- /dev/null
> +++ b/tests/qemu-iotests/080
> @@ -0,0 +1,175 @@
> +#!/usr/bin/env python
> +#
> +# Tests for IO throttling
> +#
> +# Copyright (C) 2014 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 time
> +import os
> +import iotests
> +from iotests import qemu_img
> +
> +test_img = os.path.join(iotests.test_dir, 'test.img')
> +
> +class ThrottleTestCase(iotests.QMPTestCase):
> +
> + 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):
> + qemu_img('create', '-f', iotests.imgfmt, test_img, "1G")
> + self.vm = iotests.VM().add_drive(test_img)
> + self.vm.launch()
> +
> + def tearDown(self):
> + self.vm.shutdown()
> + os.remove(test_img)
> +
> + def do_test_throttle(self, seconds=20, **limits):
> + def check_limit(limit, num):
> + # IO throttling algorithm is discrete, allow 10% error so the
> test
> + # is more deterministic
> + v = limit * seconds
> + return limit == 0 or v * 0.9 <= num <= v * 1.1
> +
> + nsec_per_sec = 1000000000
> +
> + # With current interface we can't set burst to 0, they will be
> override
> + # to bps / 10 and iops / 10. Setting to 1 workarounds this and gets
> to
> + # a close effect as no burst, which is good enough for us
> + limits['bps_max'] = 1
> + limits['iops_max'] = 1
> +
> + result = self.vm.qmp("block_set_io_throttle", conv_keys=False,
> **limits)
> + self.assert_qmp(result, 'return', {})
> +
> + # Set vm clock to a known value
> + ns = nsec_per_sec
> + self.vm.qtest("clock_step %d" % ns)
> +
> + # Append more than needed requests into the throttle queue, they
> should
> + # drain bps_max and iops_max.
> + # The remaining requests won't get executed until qtest clock is
> driven
> + n = max(limits['iops'],
> + limits['iops_rd'],
> + limits['iops_wr'],
> + limits['bps'] / 512,
> + limits['bps_rd'] / 512,
> + limits['bps_wr'] / 512) * seconds + 100
> + for i in range(n):
> + self.vm.hmp_qemu_io("drive0", "aio_read -q 0 512")
> + self.vm.hmp_qemu_io("drive0", "aio_write -q 0 512")
> +
> + start_rd_bytes, start_rd_iops, start_wr_bytes, start_wr_iops =
> self.blockstats('drive0')
> +
> + ns += seconds * nsec_per_sec
> + self.vm.qtest("clock_step %d" % ns)
> + # wait for a while to let requests take off
> + time.sleep(1)
> + end_rd_bytes, end_rd_iops, end_wr_bytes, end_wr_iops =
> self.blockstats('drive0')
> +
> + # Read and write requests should be processed
> + assert end_rd_bytes > 0
> + assert end_rd_iops > 0
> + assert end_wr_bytes > 0
> + assert end_wr_iops > 0
> +
> + 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
> +
> + assert check_limit(limits['bps'], rd_bytes + wr_bytes)
> + assert check_limit(limits['bps_rd'], rd_bytes)
> + assert check_limit(limits['bps_wr'], wr_bytes)
> + assert check_limit(limits['iops'], rd_iops + wr_iops)
> + assert check_limit(limits['iops_rd'], rd_iops)
> + assert check_limit(limits['iops_wr'], wr_iops)
> +
> + def test_bps(self):
> + self.do_test_throttle(**{
> + 'device': 'drive0',
> + 'bps': 1024,
> + 'bps_rd': 0,
> + 'bps_wr': 0,
> + 'iops': 0,
> + 'iops_rd': 0,
> + 'iops_wr': 0,
> + })
> +
> + def test_bps_rd(self):
> + self.do_test_throttle(**{
> + 'device': 'drive0',
> + 'bps': 0,
> + 'bps_rd': 1024,
> + 'bps_wr': 0,
> + 'iops': 0,
> + 'iops_rd': 0,
> + 'iops_wr': 0,
> + })
> +
> + def test_bps_wr(self):
> + self.do_test_throttle(**{
> + 'device': 'drive0',
> + 'bps': 0,
> + 'bps_rd': 0,
> + 'bps_wr': 1024,
> + 'iops': 0,
> + 'iops_rd': 0,
> + 'iops_wr': 0,
> + })
> +
> + def test_iops(self):
> + self.do_test_throttle(**{
> + 'device': 'drive0',
> + 'bps': 0,
> + 'bps_rd': 0,
> + 'bps_wr': 0,
> + 'iops': 10,
> + 'iops_rd': 0,
> + 'iops_wr': 0,
> + })
> +
> + def test_iops_rd(self):
> + self.do_test_throttle(**{
> + 'device': 'drive0',
> + 'bps': 0,
> + 'bps_rd': 0,
> + 'bps_wr': 0,
> + 'iops': 0,
> + 'iops_rd': 10,
> + 'iops_wr': 0,
> + })
> +
> + def test_iops_wr(self):
> + self.do_test_throttle(**{
> + 'device': 'drive0',
> + 'bps': 0,
> + 'bps_rd': 0,
> + 'bps_wr': 0,
> + 'iops': 0,
> + 'iops_rd': 0,
> + 'iops_wr': 10,
> + })
> +
> +if __name__ == '__main__':
> + iotests.main()
> diff --git a/tests/qemu-iotests/080.out b/tests/qemu-iotests/080.out
> new file mode 100644
> index 0000000..3f8a935
> --- /dev/null
> +++ b/tests/qemu-iotests/080.out
> @@ -0,0 +1,5 @@
> +......
> +----------------------------------------------------------------------
> +Ran 6 tests
> +
> +OK
> diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
> index 03c762f..013a7ef 100644
> --- a/tests/qemu-iotests/group
> +++ b/tests/qemu-iotests/group
> @@ -82,3 +82,4 @@
> 073 rw auto
> 074 rw auto
> 077 rw auto
> +080 rw auto
> --
> 1.8.5.4
>
Reviewed-by: Benoit Canet <ben...@irqsave.net>
