-# Copyright (c) 2016 Cisco and/or its affiliates.
+# Copyright (c) 2018 Cisco and/or its affiliates.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
-from ssh import SSH
+
+"""Performance testing traffic generator library."""
+
from robot.api import logger
+from robot.libraries.BuiltIn import BuiltIn
+
+from .DropRateSearch import DropRateSearch
+from .constants import Constants
+from .ssh import SSH
+from .topology import NodeType
+from .topology import NodeSubTypeTG
+from .topology import Topology
+from .MLRsearch.AbstractMeasurer import AbstractMeasurer
+from .MLRsearch.MultipleLossRatioSearch import MultipleLossRatioSearch
+from .MLRsearch.ReceiveRateMeasurement import ReceiveRateMeasurement
+
+__all__ = ['TGDropRateSearchImpl', 'TrafficGenerator', 'OptimizedSearch']
+
+
+class TGDropRateSearchImpl(DropRateSearch):
+ """Drop Rate Search implementation."""
+
+ def __init__(self):
+ super(TGDropRateSearchImpl, self).__init__()
+
+ def measure_loss(self, rate, frame_size, loss_acceptance,
+ loss_acceptance_type, traffic_type, skip_warmup=False):
+ """Runs the traffic and evaluate the measured results.
+
+ :param rate: Offered traffic load.
+ :param frame_size: Size of frame.
+ :param loss_acceptance: Permitted drop ratio or frames count.
+ :param loss_acceptance_type: Type of permitted loss.
+ :param traffic_type: Module name as a traffic type identifier.
+ See resources/traffic_profiles/trex for implemented modules.
+ :param skip_warmup: Start TRex without warmup traffic if true.
+ :type rate: float
+ :type frame_size: str
+ :type loss_acceptance: float
+ :type loss_acceptance_type: LossAcceptanceType
+ :type traffic_type: str
+ :type skip_warmup: bool
+ :returns: Drop threshold exceeded? (True/False)
+ :rtype: bool
+ :raises NotImplementedError: If TG is not supported.
+ :raises RuntimeError: If TG is not specified.
+ """
+ # we need instance of TrafficGenerator instantiated by Robot Framework
+ # to be able to use trex_stl-*()
+ tg_instance = BuiltIn().get_library_instance(
+ 'resources.libraries.python.TrafficGenerator')
-__all__ = ['TrafficGenerator']
+ if tg_instance.node['subtype'] is None:
+ raise RuntimeError('TG subtype not defined')
+ elif tg_instance.node['subtype'] == NodeSubTypeTG.TREX:
+ unit_rate = str(rate) + self.get_rate_type_str()
+ if skip_warmup:
+ tg_instance.trex_stl_start_remote_exec(self.get_duration(),
+ unit_rate, frame_size,
+ traffic_type,
+ warmup_time=0.0)
+ else:
+ tg_instance.trex_stl_start_remote_exec(self.get_duration(),
+ unit_rate, frame_size,
+ traffic_type)
+ loss = tg_instance.get_loss()
+ sent = tg_instance.get_sent()
+ if self.loss_acceptance_type_is_percentage():
+ loss = (float(loss) / float(sent)) * 100
-class TrafficGenerator(object):
+ logger.trace("comparing: {} < {} {}".format(loss,
+ loss_acceptance,
+ loss_acceptance_type))
+ if float(loss) > float(loss_acceptance):
+ return False
+ else:
+ return True
+ else:
+ raise NotImplementedError("TG subtype not supported")
+
+ def get_latency(self):
+ """Returns min/avg/max latency.
+
+ :returns: Latency stats.
+ :rtype: list
+ """
+ tg_instance = BuiltIn().get_library_instance(
+ 'resources.libraries.python.TrafficGenerator')
+ return tg_instance.get_latency_int()
+
+
+class TrafficGenerator(AbstractMeasurer):
+ """Traffic Generator.
+
+ FIXME: Describe API."""
+
+ # TODO: Decrease friction between various search and rate provider APIs.
+ # FIXME: Remove "trex" from lines which could work with other TGs.
+
+ # use one instance of TrafficGenerator for all tests in test suite
+ ROBOT_LIBRARY_SCOPE = 'TEST SUITE'
def __init__(self):
self._result = None
self._loss = None
self._sent = None
+ self._latency = None
self._received = None
+ self._node = None
+ # T-REX interface order mapping
+ self._ifaces_reordered = False
+ # Parameters not given by measure().
+ self.frame_size = None
+ self.traffic_type = None
+ self.warmup_time = None
+
+ @property
+ def node(self):
+ """Getter.
+
+ :returns: Traffic generator node.
+ :rtype: dict
+ """
+ return self._node
+
+ def get_loss(self):
+ """Return number of lost packets.
+
+ :returns: Number of lost packets.
+ :rtype: str
+ """
+ return self._loss
+
+ def get_sent(self):
+ """Return number of sent packets.
+
+ :returns: Number of sent packets.
+ :rtype: str
+ """
+ return self._sent
+
+ def get_received(self):
+ """Return number of received packets.
+
+ :returns: Number of received packets.
+ :rtype: str
+ """
+ return self._received
+
+ def get_latency_int(self):
+ """Return rounded min/avg/max latency.
+
+ :returns: Latency stats.
+ :rtype: list
+ """
+ return self._latency
+
+ def initialize_traffic_generator(self, tg_node, tg_if1, tg_if2,
+ tg_if1_adj_node, tg_if1_adj_if,
+ tg_if2_adj_node, tg_if2_adj_if,
+ test_type,
+ tg_if1_dst_mac=None, tg_if2_dst_mac=None):
+ """TG initialization.
+
+ :param tg_node: Traffic generator node.
+ :param tg_if1: TG - name of first interface.
+ :param tg_if2: TG - name of second interface.
+ :param tg_if1_adj_node: TG if1 adjecent node.
+ :param tg_if1_adj_if: TG if1 adjecent interface.
+ :param tg_if2_adj_node: TG if2 adjecent node.
+ :param tg_if2_adj_if: TG if2 adjecent interface.
+ :param test_type: 'L2', 'L3' or 'L7' - OSI Layer testing type.
+ :param tg_if1_dst_mac: Interface 1 destination MAC address.
+ :param tg_if2_dst_mac: Interface 2 destination MAC address.
+ :type tg_node: dict
+ :type tg_if1: str
+ :type tg_if2: str
+ :type tg_if1_adj_node: dict
+ :type tg_if1_adj_if: str
+ :type tg_if2_adj_node: dict
+ :type tg_if2_adj_if: str
+ :type test_type: str
+ :type tg_if1_dst_mac: str
+ :type tg_if2_dst_mac: str
+ :returns: nothing
+ :raises RuntimeError: In case of issue during initialization.
+ """
+ if tg_node['type'] != NodeType.TG:
+ raise RuntimeError('Node type is not a TG')
+ self._node = tg_node
+
+ if tg_node['subtype'] == NodeSubTypeTG.TREX:
+ ssh = SSH()
+ ssh.connect(tg_node)
+
+ (ret, _, _) = ssh.exec_command(
+ "sudo -E sh -c '{0}/resources/tools/trex/"
+ "trex_installer.sh {1}'".format(Constants.REMOTE_FW_DIR,
+ Constants.TREX_INSTALL_VERSION),
+ timeout=1800)
+ if int(ret) != 0:
+ raise RuntimeError('TRex installation failed.')
+
+ if1_pci = Topology().get_interface_pci_addr(tg_node, tg_if1)
+ if2_pci = Topology().get_interface_pci_addr(tg_node, tg_if2)
+ if1_addr = Topology().get_interface_mac(tg_node, tg_if1)
+ if2_addr = Topology().get_interface_mac(tg_node, tg_if2)
+
+ if test_type == 'L2':
+ if1_adj_addr = if2_addr
+ if2_adj_addr = if1_addr
+ elif test_type == 'L3':
+ if1_adj_addr = Topology().get_interface_mac(tg_if1_adj_node,
+ tg_if1_adj_if)
+ if2_adj_addr = Topology().get_interface_mac(tg_if2_adj_node,
+ tg_if2_adj_if)
+ elif test_type == 'L7':
+ if1_addr = Topology().get_interface_ip4(tg_node, tg_if1)
+ if2_addr = Topology().get_interface_ip4(tg_node, tg_if2)
+ if1_adj_addr = Topology().get_interface_ip4(tg_if1_adj_node,
+ tg_if1_adj_if)
+ if2_adj_addr = Topology().get_interface_ip4(tg_if2_adj_node,
+ tg_if2_adj_if)
+ else:
+ raise ValueError("Unknown Test Type")
+
+ # in case of switched environment we can override MAC addresses
+ if tg_if1_dst_mac is not None and tg_if2_dst_mac is not None:
+ if1_adj_addr = tg_if1_dst_mac
+ if2_adj_addr = tg_if2_dst_mac
+
+ if min(if1_pci, if2_pci) != if1_pci:
+ if1_pci, if2_pci = if2_pci, if1_pci
+ if1_addr, if2_addr = if2_addr, if1_addr
+ if1_adj_addr, if2_adj_addr = if2_adj_addr, if1_adj_addr
+ self._ifaces_reordered = True
+
+ if test_type == 'L2' or test_type == 'L3':
+ (ret, _, _) = ssh.exec_command(
+ "sudo sh -c 'cat << EOF > /etc/trex_cfg.yaml\n"
+ "- port_limit: 2\n"
+ " version: 2\n"
+ " interfaces: [\"{0}\",\"{1}\"]\n"
+ " port_info:\n"
+ " - dest_mac: [{2}]\n"
+ " src_mac: [{3}]\n"
+ " - dest_mac: [{4}]\n"
+ " src_mac: [{5}]\n"
+ "EOF'"\
+ .format(if1_pci, if2_pci,
+ "0x"+if1_adj_addr.replace(":", ",0x"),
+ "0x"+if1_addr.replace(":", ",0x"),
+ "0x"+if2_adj_addr.replace(":", ",0x"),
+ "0x"+if2_addr.replace(":", ",0x")))
+ elif test_type == 'L7':
+ (ret, _, _) = ssh.exec_command(
+ "sudo sh -c 'cat << EOF > /etc/trex_cfg.yaml\n"
+ "- port_limit: 2\n"
+ " version: 2\n"
+ " interfaces: [\"{0}\",\"{1}\"]\n"
+ " port_info:\n"
+ " - ip: [{2}]\n"
+ " default_gw: [{3}]\n"
+ " - ip: [{4}]\n"
+ " default_gw: [{5}]\n"
+ "EOF'"\
+ .format(if1_pci, if2_pci,
+ if1_addr, if1_adj_addr,
+ if2_addr, if2_adj_addr))
+ else:
+ raise ValueError("Unknown Test Type")
+ if int(ret) != 0:
+ raise RuntimeError('TRex config generation error')
+
+ for _ in range(0, 3):
+ # kill TRex only if it is already running
+ ssh.exec_command(
+ "sh -c 'pgrep t-rex && sudo pkill t-rex && sleep 3'")
+
+ # configure TRex
+ (ret, _, _) = ssh.exec_command(
+ "sh -c 'cd {0}/scripts/ && sudo ./trex-cfg'"\
+ .format(Constants.TREX_INSTALL_DIR))
+ if int(ret) != 0:
+ raise RuntimeError('trex-cfg failed')
+
+ # start TRex
+ if test_type == 'L2' or test_type == 'L3':
+ (ret, _, _) = ssh.exec_command(
+ "sh -c 'cd {0}/scripts/ && "
+ "sudo nohup ./t-rex-64 -i -c 7 --iom 0 > /tmp/trex.log "
+ "2>&1 &' > /dev/null"\
+ .format(Constants.TREX_INSTALL_DIR))
+ elif test_type == 'L7':
+ (ret, _, _) = ssh.exec_command(
+ "sh -c 'cd {0}/scripts/ && "
+ "sudo nohup ./t-rex-64 --astf -i -c 7 --iom 0 > "
+ "/tmp/trex.log 2>&1 &' > /dev/null"\
+ .format(Constants.TREX_INSTALL_DIR))
+ else:
+ raise ValueError("Unknown Test Type")
+ if int(ret) != 0:
+ ssh.exec_command("sh -c 'cat /tmp/trex.log'")
+ raise RuntimeError('t-rex-64 startup failed')
+ # get TRex server info
+ (ret, _, _) = ssh.exec_command(
+ "sh -c 'sleep 3; "
+ "{0}/resources/tools/trex/trex_server_info.py'"\
+ .format(Constants.REMOTE_FW_DIR),
+ timeout=120)
+ if int(ret) == 0:
+ # If we get info TRex is running
+ return
+ # after max retries TRex is still not responding to API
+ # critical error occurred
+ raise RuntimeError('t-rex-64 startup failed')
- def send_traffic_on(self, node, tx_port, rx_port, duration, rate,
- framesize):
+ @staticmethod
+ def is_trex_running(node):
+ """Check if TRex is running using pidof.
+
+ :param node: Traffic generator node.
+ :type node: dict
+ :returns: True if TRex is running otherwise False.
+ :rtype: bool
+ :raises RuntimeError: If node type is not a TG.
+ """
+ if node['type'] != NodeType.TG:
+ raise RuntimeError('Node type is not a TG')
+
+ ssh = SSH()
+ ssh.connect(node)
+ ret, _, _ = ssh.exec_command_sudo("pidof t-rex")
+ return bool(int(ret) == 0)
+
+ @staticmethod
+ def teardown_traffic_generator(node):
+ """TG teardown.
+
+ :param node: Traffic generator node.
+ :type node: dict
+ :returns: nothing
+ :raises RuntimeError: If node type is not a TG,
+ or if TRex teardown fails.
+ """
+ if node['type'] != NodeType.TG:
+ raise RuntimeError('Node type is not a TG')
+ if node['subtype'] == NodeSubTypeTG.TREX:
+ ssh = SSH()
+ ssh.connect(node)
+ (ret, _, _) = ssh.exec_command(
+ "sh -c 'sudo pkill t-rex && sleep 3'")
+ if int(ret) != 0:
+ raise RuntimeError('pkill t-rex failed')
+
+ @staticmethod
+ def trex_stl_stop_remote_exec(node):
+ """Execute script on remote node over ssh to stop running traffic.
+
+ :param node: TRex generator node.
+ :type node: dict
+ :returns: Nothing
+ :raises RuntimeError: If stop traffic script fails.
+ """
ssh = SSH()
ssh.connect(node)
- (ret, stdout, stderr) = ssh.exec_command(
- "sh -c 'cd MoonGen && sudo -S build/MoonGen "
- "rfc2544/benchmarks/vpp-frameloss.lua --txport 0 --rxport 1 "
- "--duration {0} --rate {1} --framesize {2}'".format(
- duration, rate, framesize),
- timeout=int(duration)+60)
+ (ret, _, _) = ssh.exec_command(
+ "sh -c '{}/resources/tools/trex/"
+ "trex_stateless_stop.py'".format(Constants.REMOTE_FW_DIR))
+
+ if int(ret) != 0:
+ raise RuntimeError('TRex stateless runtime error')
+
+ def trex_stl_start_remote_exec(self, duration, rate, framesize,
+ traffic_type, async_call=False,
+ latency=True, warmup_time=5.0):
+ """Execute script on remote node over ssh to start traffic.
+
+ :param duration: Time expresed in seconds for how long to send traffic.
+ :param rate: Traffic rate expressed with units (pps, %)
+ :param framesize: L2 frame size to send (without padding and IPG).
+ :param traffic_type: Module name as a traffic type identifier.
+ See resources/traffic_profiles/trex for implemented modules.
+ :param async_call: If enabled then don't wait for all incomming trafic.
+ :param latency: With latency measurement.
+ :param warmup_time: Warmup time period.
+ :type duration: float
+ :type rate: str
+ :type framesize: str
+ :type traffic_type: str
+ :type async_call: bool
+ :type latency: bool
+ :type warmup_time: float
+ :returns: Nothing
+ :raises RuntimeError: In case of TG driver issue.
+ """
+ ssh = SSH()
+ ssh.connect(self._node)
+
+ _async = "--async" if async_call else ""
+ _latency = "--latency" if latency else ""
+ _p0, _p1 = (2, 1) if self._ifaces_reordered else (1, 2)
+
+ profile_path = ("{0}/resources/traffic_profiles/trex/"
+ "{1}.py".format(Constants.REMOTE_FW_DIR,
+ traffic_type))
+ (ret, stdout, _) = ssh.exec_command(
+ "sh -c "
+ "'{0}/resources/tools/trex/trex_stateless_profile.py "
+ "--profile {1} "
+ "--duration {2} "
+ "--frame_size {3} "
+ "--rate {4} "
+ "--warmup_time {5} "
+ "--port_0 {6} "
+ "--port_1 {7} "
+ "{8} " # --async
+ "{9}'". # --latency
+ format(Constants.REMOTE_FW_DIR, profile_path, duration, framesize,
+ rate, warmup_time, _p0 - 1, _p1 - 1, _async, _latency),
+ timeout=float(duration) + 60)
+
+ if int(ret) != 0:
+ raise RuntimeError('TRex stateless runtime error')
+ elif async_call:
+ #no result
+ self._received = None
+ self._sent = None
+ self._loss = None
+ self._latency = None
+ else:
+ # last line from console output
+ line = stdout.splitlines()[-1]
+
+ self._result = line
+ logger.info('TrafficGen result: {0}'.format(self._result))
+
+ self._received = self._result.split(', ')[1].split('=')[1]
+ self._sent = self._result.split(', ')[2].split('=')[1]
+ self._loss = self._result.split(', ')[3].split('=')[1]
+
+ self._latency = []
+ self._latency.append(self._result.split(', ')[4].split('=')[1])
+ self._latency.append(self._result.split(', ')[5].split('=')[1])
+
+ def stop_traffic_on_tg(self):
+ """Stop all traffic on TG.
+
+ :returns: Nothing
+ :raises RuntimeError: If TG is not set.
+ """
+ if self._node is None:
+ raise RuntimeError("TG is not set")
+ if self._node['subtype'] == NodeSubTypeTG.TREX:
+ self.trex_stl_stop_remote_exec(self._node)
- logger.trace(ret)
- logger.trace(stdout)
- logger.trace(stderr)
+ def send_traffic_on_tg(self, duration, rate, framesize,
+ traffic_type, warmup_time=5, async_call=False,
+ latency=True):
+ """Send traffic from all configured interfaces on TG.
- for line in stdout.splitlines():
- pass
+ :param duration: Duration of test traffic generation in seconds.
+ :param rate: Offered load per interface (e.g. 1%, 3gbps, 4mpps, ...).
+ :param framesize: Frame size (L2) in Bytes.
+ :param traffic_type: Module name as a traffic type identifier.
+ See resources/traffic_profiles/trex for implemented modules.
+ :param warmup_time: Warmup phase in seconds.
+ :param async_call: Async mode.
+ :param latency: With latency measurement.
+ :type duration: str
+ :type rate: str
+ :type framesize: str
+ :type traffic_type: str
+ :type warmup_time: float
+ :type async_call: bool
+ :type latency: bool
+ :returns: TG output.
+ :rtype: str
+ :raises RuntimeError: If TG is not set, or if node is not TG,
+ or if subtype is not specified.
+ :raises NotImplementedError: If TG is not supported.
+ """
- self._result = line
- logger.info('TrafficGen result: {0}'.format(self._result))
+ node = self._node
+ if node is None:
+ raise RuntimeError("TG is not set")
- self._loss = self._result.split(', ')[3].split('=')[1]
+ if node['type'] != NodeType.TG:
+ raise RuntimeError('Node type is not a TG')
+
+ if node['subtype'] is None:
+ raise RuntimeError('TG subtype not defined')
+ elif node['subtype'] == NodeSubTypeTG.TREX:
+ self.trex_stl_start_remote_exec(duration, rate, framesize,
+ traffic_type, async_call, latency,
+ warmup_time=warmup_time)
+ else:
+ raise NotImplementedError("TG subtype not supported")
return self._result
- def no_traffic_loss_occured(self):
+ def no_traffic_loss_occurred(self):
+ """Fail if loss occurred in traffic run.
+
+ :returns: nothing
+ :raises Exception: If loss occured.
+ """
if self._loss is None:
- raise Exception('The traffic generation has not been issued')
+ raise RuntimeError('The traffic generation has not been issued')
if self._loss != '0':
- raise Exception('Traffic loss occured: {0}'.format(self._loss))
+ raise RuntimeError('Traffic loss occurred: {0}'.format(self._loss))
+
+ def fail_if_no_traffic_forwarded(self):
+ """Fail if no traffic forwarded.
+
+ :returns: nothing
+ :raises Exception: If no traffic forwarded.
+ """
+ if self._received is None:
+ raise RuntimeError('The traffic generation has not been issued')
+ if self._received == '0':
+ raise RuntimeError('No traffic forwarded')
+
+ def partial_traffic_loss_accepted(self, loss_acceptance,
+ loss_acceptance_type):
+ """Fail if loss is higher then accepted in traffic run.
+
+ :param loss_acceptance: Permitted drop ratio or frames count.
+ :param loss_acceptance_type: Type of permitted loss.
+ :type loss_acceptance: float
+ :type loss_acceptance_type: LossAcceptanceType
+ :returns: nothing
+ :raises Exception: If loss is above acceptance criteria.
+ """
+ if self._loss is None:
+ raise Exception('The traffic generation has not been issued')
+
+ if loss_acceptance_type == 'percentage':
+ loss = (float(self._loss) / float(self._sent)) * 100
+ elif loss_acceptance_type == 'frames':
+ loss = float(self._loss)
+ else:
+ raise Exception('Loss acceptance type not supported')
+
+ if loss > float(loss_acceptance):
+ raise Exception("Traffic loss {} above loss acceptance: {}".format(
+ loss, loss_acceptance))
+
+ def set_rate_provider_defaults(self, frame_size, traffic_type,
+ warmup_time=0.0):
+ """Store values accessed by measure().
+
+ :param frame_size: Frame size identifier or value [B].
+ :param traffic_type: Module name as a traffic type identifier.
+ See resources/traffic_profiles/trex for implemented modules.
+ :param warmup_time: Traffic duration before measurement starts [s].
+ :type frame_size: str or int
+ :type traffic_type: str
+ :type warmup_time: float
+ """
+ self.frame_size = frame_size
+ self.traffic_type = str(traffic_type)
+ self.warmup_time = float(warmup_time)
+
+ def measure(self, duration, transmit_rate):
+ """Run bi-directional measurement, parse and return results.
+
+ :param duration: Trial duration [s].
+ :param transmit_rate: Target bidirectional transmit rate [pps].
+ :type duration: float
+ :type transmit_rate: float
+ :returns: Structure containing the result of the measurement.
+ :rtype: ReceiveRateMeasurement
+ :raises RuntimeError: If TG is not set, or if node is not TG,
+ or if subtype is not specified.
+ :raises NotImplementedError: If TG is not supported.
+ """
+ duration = float(duration)
+ transmit_rate = float(transmit_rate)
+ # Trex needs target Tr per stream, but reports aggregate Tx and Dx.
+ unit_rate = str(transmit_rate / 2.0) + "pps"
+ self.send_traffic_on_tg(
+ duration, unit_rate, self.frame_size, self.traffic_type,
+ self.warmup_time, latency=True)
+ transmit_count = int(self.get_sent())
+ loss_count = int(self.get_loss())
+ measurement = ReceiveRateMeasurement(
+ duration, transmit_rate, transmit_count, loss_count)
+ measurement.latency = self.get_latency_int()
+ return measurement
+
+
+class OptimizedSearch(object):
+ """Class to be imported as Robot Library, containing a single keyword."""
+
+ @staticmethod
+ def perform_optimized_ndrpdr_search(
+ frame_size, traffic_type, minimum_transmit_rate,
+ maximum_transmit_rate, packet_loss_ratio=0.005,
+ final_relative_width=0.005, final_trial_duration=30.0,
+ initial_trial_duration=1.0, number_of_intermediate_phases=2,
+ timeout=720.0, doublings=1):
+ """Setup initialized TG, perform optimized search, return intervals.
+
+ :param frame_size: Frame size identifier or value [B].
+ :param traffic_type: Module name as a traffic type identifier.
+ See resources/traffic_profiles/trex for implemented modules.
+ :param minimum_transmit_rate: Minimal bidirectional
+ target transmit rate [pps].
+ :param maximum_transmit_rate: Maximal bidirectional
+ target transmit rate [pps].
+ :param packet_loss_ratio: Fraction of packets lost, for PDR [1].
+ :param final_relative_width: Final lower bound transmit rate
+ cannot be more distant that this multiple of upper bound [1].
+ :param final_trial_duration: Trial duration for the final phase [s].
+ :param initial_trial_duration: Trial duration for the initial phase
+ and also for the first intermediate phase [s].
+ :param number_of_intermediate_phases: Number of intermediate phases
+ to perform before the final phase [1].
+ :param timeout: The search will fail itself when not finished
+ before this overall time [s].
+ :param doublings: How many doublings to do in external search step.
+ Default 1 is suitable for fairly stable tests,
+ less stable tests might get better overal duration with 2 or more.
+ :type frame_size: str or int
+ :type traffic_type: str
+ :type minimum_transmit_rate: float
+ :type maximum_transmit_rate: float
+ :type packet_loss_ratio: float
+ :type final_relative_width: float
+ :type final_trial_duration: float
+ :type initial_trial_duration: float
+ :type number_of_intermediate_phases: int
+ :type timeout: float
+ :type doublings: int
+ :returns: Structure containing narrowed down NDR and PDR intervals
+ and their measurements.
+ :rtype: NdrPdrResult
+ :raises RuntimeError: If total duration is larger than timeout.
+ """
+ # we need instance of TrafficGenerator instantiated by Robot Framework
+ # to be able to use trex_stl-*()
+ tg_instance = BuiltIn().get_library_instance(
+ 'resources.libraries.python.TrafficGenerator')
+ tg_instance.set_rate_provider_defaults(frame_size, traffic_type)
+ algorithm = MultipleLossRatioSearch(
+ measurer=tg_instance, final_trial_duration=final_trial_duration,
+ final_relative_width=final_relative_width,
+ number_of_intermediate_phases=number_of_intermediate_phases,
+ initial_trial_duration=initial_trial_duration, timeout=timeout,
+ doublings=doublings)
+ result = algorithm.narrow_down_ndr_and_pdr(
+ minimum_transmit_rate, maximum_transmit_rate, packet_loss_ratio)
+ return result