x/whitebox-neutron-tempest-plugin
Code Issues Proposed changes

Adapt BW limit tests to traffic shaping

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With recent neutron changes, traffic shaping is applied when network
type is either vlan or flat when BW limit is configured.

BW limit tests have been adapted to the new algoritm to avoid dropping
iperf control packets that make tests fail. Those packets could be
dropped because shaper buffers drop packets when bitrate exceeds the
configured BW limit. In order to avoid this:
- Injected bitrate, which exceeds the configured BW limit, is limitted
  to 1.5 * bwlimit
- iperf tests duration is limitted to 6 seconds (the shorted the iperf
  tests, the less likely shaper buffers get full)

Change-Id: Icc1e1eb333a8844d7ddcf7a17ccc48886b3889e1
This commit is contained in:
Eduardo Olivares 2025-04-03 13:02:30 +02:00
parent 2ad8456264
commit d43e56466a
1 changed files with 24 additions and 13 deletions
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37
whitebox_neutron_tempest_plugin/tests/scenario/test_qos.py
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@ -176,7 +176,8 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
raise ValueError('Unsupported protocol %s' % protocol)
def _test_egress_bw(
self, ssh_client, ssh_server, server_ip, protocol, timeout=10):
self, ssh_client, ssh_server, server_ip, protocol, maxbitrate,
timeout=6):
utils.kill_iperf_process(ssh_server)
utils.kill_iperf_process(ssh_client)
@ -196,7 +197,7 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
port=self.IPERF_PORT,
protocol_param=protocol_param,
timeout=timeout,
maxbitrate=self.MIN_KBPS_NO_BWLIMIT * 2000))
maxbitrate=maxbitrate))
LOG.debug('Run iperf3 command on client: %s', client_cmd)
ssh_client.exec_command(client_cmd)
time.sleep(0.1)
@ -204,7 +205,8 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
ssh_server, iperf_server_filename))
def _test_ingress_bw(
self, ssh_client, ssh_server, server_ip, protocol, timeout=10):
self, ssh_client, ssh_server, server_ip, protocol, maxbitrate,
timeout=6):
utils.kill_iperf_process(ssh_server)
utils.kill_iperf_process(ssh_client)
@ -220,7 +222,7 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
'-R -J > {output_file}'.format(
server_ip=server_ip, port=self.IPERF_PORT,
protocol_param=protocol_param, timeout=timeout,
maxbitrate=self.MIN_KBPS_NO_BWLIMIT * 2000,
maxbitrate=maxbitrate,
output_file=iperf_client_filename))
LOG.debug('Run iperf3 command on client: %s', client_cmd)
ssh_client.exec_command(client_cmd)
@ -229,6 +231,13 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
ssh_client, iperf_client_filename))
def _calculate_bw(self, perf_measures):
# For rocky images, final interval is ignored
# TODO(eolivare): provide link to iperf/rocky bug
intervals_end = (len(perf_measures['intervals'])
if self.username != "rocky"
else len(perf_measures['intervals']) - 1)
intervals = perf_measures['intervals'][:intervals_end]
# First 3 for ovs envs, 2 for ovn sriov envs and 1 for normal ovn
# intervals are removed because BW measured during it is not
# limited - it takes ~2-4 seconds to traffic shaping algorithm to apply
@ -240,14 +249,8 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
intervals_start = 2
else:
intervals_start = 1
# For rocky images, final interval is ignored
# TODO(eolivare): provide link to iperf/rocky bug
intervals_end = (len(perf_measures['intervals'])
if self.username != "rocky"
else len(perf_measures['intervals']) - 1)
intervals = perf_measures['intervals'][intervals_start:intervals_end]
if len(intervals) > intervals_start + 1:
intervals = intervals[intervals_start:]
bits_received = sum([interval['sum']['bytes'] * 8
for interval in intervals])
@ -284,12 +287,20 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
test_bw_method = self._test_ingress_bw
direction = 'ingress'
# NOTE: with traffic shaping, if the bitrate exceeds the BW limit, the
# excees traffic is buffered and sent once the iperf3 client has ended
# sending traffic, but this could lead to an iperf error:
# "control socket has closed unexpectedly"
# due to this we limit the bitrate to 1.5 * bw_limit
maxbitrate = (bw_limit * 1.5 if bw_limit is not None
else self.MIN_KBPS_NO_BWLIMIT * 2000)
# egress: send payload from client to server
# ingress: download payload from server to client
for server_ip in server_ips:
perf_measures = test_bw_method(
client['ssh_client'], server['ssh_client'],
server_ip, protocol)
server_ip, protocol, maxbitrate=maxbitrate)
LOG.debug('perf_measures = %s', perf_measures)
# verify bw limit