Soak: Do not allow negative loss

[csit.git] / resources / libraries / python / TrafficGenerator.py

diff --git a/resources/libraries/python/TrafficGenerator.py b/resources/libraries/python/TrafficGenerator.py
index 751dc88..c5192e2 100644 (file)
--- a/resources/libraries/python/TrafficGenerator.py
+++ b/resources/libraries/python/TrafficGenerator.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2019 Cisco and/or its affiliates.
+# Copyright (c) 2020 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:
 # 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:


@@ -18,18 +18,20 @@ import time
 from robot.api import logger
 from robot.libraries.BuiltIn import BuiltIn
 
 from robot.api import logger
 from robot.libraries.BuiltIn import BuiltIn
 

-from .DropRateSearch import DropRateSearch

 from .Constants import Constants
 from .Constants import Constants

-from .ssh import exec_cmd_no_error, exec_cmd
-from .topology import NodeType
-from .topology import NodeSubTypeTG
-from .topology import Topology
+from .CpuUtils import CpuUtils
+from .DropRateSearch import DropRateSearch

 from .MLRsearch.AbstractMeasurer import AbstractMeasurer
 from .MLRsearch.MultipleLossRatioSearch import MultipleLossRatioSearch
 from .MLRsearch.ReceiveRateMeasurement import ReceiveRateMeasurement
 from .PLRsearch.PLRsearch import PLRsearch
 from .MLRsearch.AbstractMeasurer import AbstractMeasurer
 from .MLRsearch.MultipleLossRatioSearch import MultipleLossRatioSearch
 from .MLRsearch.ReceiveRateMeasurement import ReceiveRateMeasurement
 from .PLRsearch.PLRsearch import PLRsearch

+from .OptionString import OptionString
+from .ssh import exec_cmd_no_error, exec_cmd
+from .topology import NodeType
+from .topology import NodeSubTypeTG
+from .topology import Topology

 
 

-__all__ = ['TGDropRateSearchImpl', 'TrafficGenerator', 'OptimizedSearch']
+__all__ = [u"TGDropRateSearchImpl", u"TrafficGenerator", u"OptimizedSearch"]

 
 
 def check_subtype(node):
 
 
 def check_subtype(node):


@@ -44,27 +46,28 @@ def check_subtype(node):
     :rtype: NodeSubTypeTG
     :raises RuntimeError: If node is not supported, message explains how.
     """
     :rtype: NodeSubTypeTG
     :raises RuntimeError: If node is not supported, message explains how.
     """

-    if node.get('type') is None:
-        raise RuntimeError('Node type is not defined')
+    if node.get(u"type") is None:
+        msg = u"Node type is not defined"

     elif node['type'] != NodeType.TG:
     elif node['type'] != NodeType.TG:

-        raise RuntimeError('Node type is {typ!r}, not a TG'.format(
-            typ=node['type']))
-    elif node.get('subtype') is None:
-        raise RuntimeError('TG subtype is not defined')
-    elif node['subtype'] == NodeSubTypeTG.TREX:
+        msg = f"Node type is {node[u'type']!r}, not a TG"
+    elif node.get(u"subtype") is None:
+        msg = u"TG subtype is not defined"
+    elif node[u"subtype"] != NodeSubTypeTG.TREX:
+        msg = f"TG subtype {node[u'subtype']!r} is not supported"
+    else:

         return NodeSubTypeTG.TREX
         return NodeSubTypeTG.TREX

-    raise RuntimeError('TG subtype {sub!r} is not supported'.format(
-        sub=node['subtype']))
+    raise RuntimeError(msg)

 
 
 class TGDropRateSearchImpl(DropRateSearch):
     """Drop Rate Search implementation."""
 
 
 
 class TGDropRateSearchImpl(DropRateSearch):
     """Drop Rate Search implementation."""
 

-    def __init__(self):
-        super(TGDropRateSearchImpl, self).__init__()
+    # def __init__(self):
+    #     super(TGDropRateSearchImpl, self).__init__()

 
 

-    def measure_loss(self, rate, frame_size, loss_acceptance,
-                     loss_acceptance_type, traffic_profile, skip_warmup=False):
+    def measure_loss(
+            self, rate, frame_size, loss_acceptance, loss_acceptance_type,
+            traffic_profile, skip_warmup=False):

         """Runs the traffic and evaluate the measured results.
 
         :param rate: Offered traffic load.
         """Runs the traffic and evaluate the measured results.
 
         :param rate: Offered traffic load.


@@ -72,7 +75,7 @@ class TGDropRateSearchImpl(DropRateSearch):
         :param loss_acceptance: Permitted drop ratio or frames count.
         :param loss_acceptance_type: Type of permitted loss.
         :param traffic_profile: Module name as a traffic profile identifier.
         :param loss_acceptance: Permitted drop ratio or frames count.
         :param loss_acceptance_type: Type of permitted loss.
         :param traffic_profile: Module name as a traffic profile identifier.

-            See resources/traffic_profiles/trex for implemented modules.
+            See GPL/traffic_profiles/trex for implemented modules.

         :param skip_warmup: Start TRex without warmup traffic if true.
         :type rate: float
         :type frame_size: str
         :param skip_warmup: Start TRex without warmup traffic if true.
         :type rate: float
         :type frame_size: str


@@ -88,23 +91,27 @@ class TGDropRateSearchImpl(DropRateSearch):
         # we need instance of TrafficGenerator instantiated by Robot Framework
         # to be able to use trex_stl-*()
         tg_instance = BuiltIn().get_library_instance(
         # 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')
+            u"resources.libraries.python.TrafficGenerator"
+        )

         subtype = check_subtype(tg_instance.node)
         if 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_profile,
         subtype = check_subtype(tg_instance.node)
         if 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_profile,

-                    warmup_time=0.0)
+                    warmup_time=0.0
+                )

             else:
                 tg_instance.trex_stl_start_remote_exec(
             else:
                 tg_instance.trex_stl_start_remote_exec(

-                    self.get_duration(), unit_rate, frame_size, traffic_profile)
+                    self.get_duration(), unit_rate, frame_size, traffic_profile
+                )

             loss = tg_instance.get_loss()
             sent = tg_instance.get_sent()
             if self.loss_acceptance_type_is_percentage():
                 loss = (float(loss) / float(sent)) * 100
             loss = tg_instance.get_loss()
             sent = tg_instance.get_sent()
             if self.loss_acceptance_type_is_percentage():
                 loss = (float(loss) / float(sent)) * 100

-            logger.trace("comparing: {los} < {acc} {typ}".format(
-                los=loss, acc=loss_acceptance, typ=loss_acceptance_type))
+            logger.trace(
+                f"comparing: {loss} < {loss_acceptance} {loss_acceptance_type}"
+            )

             return float(loss) <= float(loss_acceptance)
         return False
 
             return float(loss) <= float(loss_acceptance)
         return False
 


@@ -115,10 +122,13 @@ class TGDropRateSearchImpl(DropRateSearch):
         :rtype: list
         """
         tg_instance = BuiltIn().get_library_instance(
         :rtype: list
         """
         tg_instance = BuiltIn().get_library_instance(

-            'resources.libraries.python.TrafficGenerator')
+            u"resources.libraries.python.TrafficGenerator"
+        )

         return tg_instance.get_latency_int()
 
 
         return tg_instance.get_latency_int()
 
 

+# TODO: Pylint says too-many-instance-attributes.
+# A fix is developed in https://gerrit.fd.io/r/c/csit/+/22221

 class TrafficGenerator(AbstractMeasurer):
     """Traffic Generator.
 
 class TrafficGenerator(AbstractMeasurer):
     """Traffic Generator.
 


@@ -128,7 +138,7 @@ class TrafficGenerator(AbstractMeasurer):
     # TODO: Remove "trex" from lines which could work with other TGs.
 
     # Use one instance of TrafficGenerator for all tests in test suite
     # TODO: 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'
+    ROBOT_LIBRARY_SCOPE = u"TEST SUITE"

 
     def __init__(self):
         # TODO: Number of fields will be reduced with CSIT-1378.
 
     def __init__(self):
         # TODO: Number of fields will be reduced with CSIT-1378.


@@ -141,6 +151,8 @@ class TrafficGenerator(AbstractMeasurer):
         self._sent = None
         self._latency = None
         self._received = None
         self._sent = None
         self._latency = None
         self._received = None

+        self._approximated_rate = None
+        self._approximated_duration = None

         # Measurement input fields, needed for async stop result.
         self._start_time = None
         self._rate = None
         # Measurement input fields, needed for async stop result.
         self._start_time = None
         self._rate = None


@@ -149,6 +161,7 @@ class TrafficGenerator(AbstractMeasurer):
         self.traffic_profile = None
         self.warmup_time = None
         self.traffic_directions = None
         self.traffic_profile = None
         self.warmup_time = None
         self.traffic_directions = None

+        self.negative_loss = None

         # Transient data needed for async measurements.
         self._xstats = (None, None)
         # TODO: Rename "xstats" to something opaque, so TRex is not privileged?
         # Transient data needed for async measurements.
         self._xstats = (None, None)
         # TODO: Rename "xstats" to something opaque, so TRex is not privileged?


@@ -194,6 +207,17 @@ class TrafficGenerator(AbstractMeasurer):
         """
         return self._latency
 
         """
         return self._latency
 

+    def get_approximated_rate(self):
+        """Return approximated rate computed as ratio of transmited packets over
+        duration of trial.
+
+        :returns: Approximated rate.
+        :rtype: str
+        """
+        return self._approximated_rate
+
+    # TODO: pylint says disable=too-many-locals.
+    # A fix is developed in https://gerrit.fd.io/r/c/csit/+/22221

     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, osi_layer, tg_if1_dst_mac=None,
     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, osi_layer, tg_if1_dst_mac=None,


@@ -234,23 +258,27 @@ class TrafficGenerator(AbstractMeasurer):
             if1_addr = Topology().get_interface_mac(self._node, tg_if1)
             if2_addr = Topology().get_interface_mac(self._node, tg_if2)
 
             if1_addr = Topology().get_interface_mac(self._node, tg_if1)
             if2_addr = Topology().get_interface_mac(self._node, tg_if2)
 

-            if osi_layer == 'L2':
+            if osi_layer == u"L2":

                 if1_adj_addr = if2_addr
                 if2_adj_addr = if1_addr
                 if1_adj_addr = if2_addr
                 if2_adj_addr = if1_addr

-            elif osi_layer == '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 osi_layer == 'L7':
+            elif osi_layer == u"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 osi_layer == u"L7":

                 if1_addr = Topology().get_interface_ip4(self._node, tg_if1)
                 if2_addr = Topology().get_interface_ip4(self._node, tg_if2)
                 if1_addr = Topology().get_interface_ip4(self._node, tg_if1)
                 if2_addr = Topology().get_interface_ip4(self._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)
+                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:
             else:

-                raise ValueError("Unknown Test Type")
+                raise ValueError(u"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:
 
             # 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:


@@ -263,98 +291,138 @@ class TrafficGenerator(AbstractMeasurer):
                 if1_adj_addr, if2_adj_addr = if2_adj_addr, if1_adj_addr
                 self._ifaces_reordered = True
 
                 if1_adj_addr, if2_adj_addr = if2_adj_addr, if1_adj_addr
                 self._ifaces_reordered = True
 

-            if osi_layer == 'L2' or osi_layer == 'L3':
+            master_thread_id, latency_thread_id, socket, threads = \
+                CpuUtils.get_affinity_trex(
+                    self._node, tg_if1, tg_if2,
+                    tg_dtc=Constants.TREX_CORE_COUNT)
+
+            if osi_layer in (u"L2", u"L3"):
+                dst_mac0 = f"0x{if1_adj_addr.replace(u':', u',0x')}"
+                src_mac0 = f"0x{if1_addr.replace(u':', u',0x')}"
+                dst_mac1 = f"0x{if2_adj_addr.replace(u':', u',0x')}"
+                src_mac1 = f"0x{if2_addr.replace(u':', u',0x')}"

                 exec_cmd_no_error(
                     self._node,
                 exec_cmd_no_error(
                     self._node,

-                    "sh -c 'cat << EOF > /etc/trex_cfg.yaml\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")),
-                    sudo=True, message='TRex config generation error')
-            elif osi_layer == 'L7':
+                    f"sh -c 'cat << EOF > /etc/trex_cfg.yaml\n"
+                    f"- version: 2\n"
+                    f"  c: {len(threads)}\n"
+                    f"  limit_memory: {Constants.TREX_LIMIT_MEMORY}\n"
+                    f"  interfaces: [\"{if1_pci}\",\"{if2_pci}\"]\n"
+                    f"  port_info:\n"
+                    f"      - dest_mac: [{dst_mac0}]\n"
+                    f"        src_mac: [{src_mac0}]\n"
+                    f"      - dest_mac: [{dst_mac1}]\n"
+                    f"        src_mac: [{src_mac1}]\n"
+                    f"  platform :\n"
+                    f"      master_thread_id: {master_thread_id}\n"
+                    f"      latency_thread_id: {latency_thread_id}\n"
+                    f"      dual_if:\n"
+                    f"          - socket: {socket}\n"
+                    f"            threads: {threads}\n"
+                    f"EOF'",
+                    sudo=True, message=u"TRex config generation!"
+                )
+            elif osi_layer == u"L7":

                 exec_cmd_no_error(
                     self._node,
                 exec_cmd_no_error(
                     self._node,

-                    "sh -c 'cat << EOF > /etc/trex_cfg.yaml\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),
-                    sudo=True, message='TRex config generation error')
+                    f"sh -c 'cat << EOF > /etc/trex_cfg.yaml\n"
+                    f"- version: 2\n"
+                    f"  c: {len(threads)}\n"
+                    f"  limit_memory: {Constants.TREX_LIMIT_MEMORY}\n"
+                    f"  interfaces: [\"{if1_pci}\",\"{if2_pci}\"]\n"
+                    f"  port_info:\n"
+                    f"      - ip: [{if1_addr}]\n"
+                    f"        default_gw: [{if1_adj_addr}]\n"
+                    f"      - ip: [{if2_addr}]\n"
+                    f"        default_gw: [{if2_adj_addr}]\n"
+                    f"  platform :\n"
+                    f"      master_thread_id: {master_thread_id}\n"
+                    f"      latency_thread_id: {latency_thread_id}\n"
+                    f"      dual_if:\n"
+                    f"          - socket: {socket}\n"
+                    f"            threads: {threads}\n"
+                    f"EOF'",
+                    sudo=True, message=u"TRex config generation!"
+                )

             else:
             else:

-                raise ValueError("Unknown Test Type")
+                raise ValueError(u"Unknown Test Type!")

 
 

-            self._startup_trex(osi_layer)
+            TrafficGenerator.startup_trex(
+                self._node, osi_layer, subtype=subtype
+            )

 
 

-    def _startup_trex(self, osi_layer):
+    @staticmethod
+    def startup_trex(tg_node, osi_layer, subtype=None):

         """Startup sequence for the TRex traffic generator.
 
         """Startup sequence for the TRex traffic generator.
 

+        :param tg_node: Traffic generator node.

         :param osi_layer: 'L2', 'L3' or 'L7' - OSI Layer testing type.
         :param osi_layer: 'L2', 'L3' or 'L7' - OSI Layer testing type.

+        :param subtype: Traffic generator sub-type.
+        :type tg_node: dict

         :type osi_layer: str
         :type osi_layer: str

+        :type subtype: NodeSubTypeTG

         :raises RuntimeError: If node subtype is not a TREX or startup failed.
         """
         :raises RuntimeError: If node subtype is not a TREX or startup failed.
         """

-        # No need to check subtype, we know it is TREX.
-        for _ in range(0, 3):
-            # Kill TRex only if it is already running.
-            cmd = "sh -c 'pgrep t-rex && pkill t-rex && sleep 3 || true'"
-            exec_cmd_no_error(
-                self._node, cmd, sudo=True, message='Kill TRex failed!')
-
-            # Configure TRex.
-            ports = ''
-            for port in self._node['interfaces'].values():
-                ports += ' {pci}'.format(pci=port.get('pci_address'))
-
-            cmd = ("sh -c 'cd {dir}/scripts/ && "
-                   "./dpdk_nic_bind.py -u {ports} || true'"
-                   .format(dir=Constants.TREX_INSTALL_DIR, ports=ports))
-            exec_cmd_no_error(
-                self._node, cmd, sudo=True,
-                message='Unbind PCI ports from driver failed!')
-
-            # Start TRex.
-            cmd = ("sh -c 'cd {dir}/scripts/ && "
-                   "nohup ./t-rex-64 --hdrh{mode} -i -c 7 > "
-                   "/tmp/trex.log 2>&1 &' > /dev/null"
-                   .format(dir=Constants.TREX_INSTALL_DIR,
-                           mode=' --astf' if osi_layer == 'L7' else ''))
-            try:
-                exec_cmd_no_error(self._node, cmd, sudo=True)
-            except RuntimeError:
-                cmd = "sh -c 'cat /tmp/trex.log'"
+        if not subtype:
+            subtype = check_subtype(tg_node)
+        if subtype == NodeSubTypeTG.TREX:
+            for _ in range(0, 3):
+                # Kill TRex only if it is already running.
+                cmd = u"sh -c \"pgrep t-rex && pkill t-rex && sleep 3 || true\""

                 exec_cmd_no_error(
                 exec_cmd_no_error(

-                    self._node, cmd, sudo=True, message='Get TRex logs failed!')
-                raise RuntimeError('Start TRex failed!')
+                    tg_node, cmd, sudo=True, message=u"Kill TRex failed!"
+                )
+
+                # Configure TRex.
+                ports = ''
+                for port in tg_node[u"interfaces"].values():
+                    ports += f" {port.get(u'pci_address')}"

 
 

-            # Test if TRex starts successfuly.
-            cmd = ("sh -c '{dir}/resources/tools/trex/trex_server_info.py'"
-                   .format(dir=Constants.REMOTE_FW_DIR))
-            try:
+                cmd = f"sh -c \"cd {Constants.TREX_INSTALL_DIR}/scripts/ && " \
+                    f"./dpdk_nic_bind.py -u {ports} || true\""

                 exec_cmd_no_error(
                 exec_cmd_no_error(

-                    self._node, cmd, sudo=True, message='Test TRex failed!',
-                    retries=20)
-            except RuntimeError:
-                continue
-            return
-        # After max retries TRex is still not responding to API critical error
-        # occurred.
-        raise RuntimeError('Start TRex failed after multiple retries!')
+                    tg_node, cmd, sudo=True,
+                    message=u"Unbind PCI ports from driver failed!"
+                )
+
+                # Start TRex.
+                cd_cmd = f"cd '{Constants.TREX_INSTALL_DIR}/scripts/'"
+                trex_cmd = OptionString([u"nohup", u"./t-rex-64"])
+                trex_cmd.add(u"-i")
+                trex_cmd.add(u"--prefix $(hostname)")
+                trex_cmd.add(u"--hdrh")
+                trex_cmd.add(u"--no-scapy-server")
+                trex_cmd.add_if(u"--astf", osi_layer == u"L7")
+                # OptionString does not create double space if extra is empty.
+                trex_cmd.add(f"{Constants.TREX_EXTRA_CMDLINE}")
+                inner_command = f"{cd_cmd} && {trex_cmd} > /tmp/trex.log 2>&1 &"
+                cmd = f"sh -c \"{inner_command}\" > /dev/null"
+                try:
+                    exec_cmd_no_error(tg_node, cmd, sudo=True)
+                except RuntimeError:
+                    cmd = u"sh -c \"cat /tmp/trex.log\""
+                    exec_cmd_no_error(
+                        tg_node, cmd, sudo=True,
+                        message=u"Get TRex logs failed!"
+                    )
+                    raise RuntimeError(u"Start TRex failed!")
+
+                # Test if TRex starts successfuly.
+                command_line = OptionString().add(u"python3")
+                dirname = f"{Constants.REMOTE_FW_DIR}/GPL/tools/trex"
+                command_line.add(f"'{dirname}/trex_server_info.py'")
+                try:
+                    exec_cmd_no_error(
+                        tg_node, command_line, sudo=True,
+                        message=u"Test TRex failed!", retries=20
+                    )
+                except RuntimeError:
+                    continue
+                return
+            # After max retries TRex is still not responding to API critical
+            # error occurred.
+            exec_cmd(tg_node, u"cat /tmp/trex.log", sudo=True)
+            raise RuntimeError(u"Start TRex failed after multiple retries!")

 
     @staticmethod
     def is_trex_running(node):
 
     @staticmethod
     def is_trex_running(node):


@@ -366,9 +434,7 @@ class TrafficGenerator(AbstractMeasurer):
         :rtype: bool
         :raises RuntimeError: If node type is not a TG.
         """
         :rtype: bool
         :raises RuntimeError: If node type is not a TG.
         """

-        # No need to check subtype, we know it is TREX.
-
-        ret, _, _ = exec_cmd(node, "pidof t-rex", sudo=True)
+        ret, _, _ = exec_cmd(node, u"pgrep t-rex", sudo=True)

         return bool(int(ret) == 0)
 
     @staticmethod
         return bool(int(ret) == 0)
 
     @staticmethod


@@ -384,8 +450,12 @@ class TrafficGenerator(AbstractMeasurer):
         subtype = check_subtype(node)
         if subtype == NodeSubTypeTG.TREX:
             exec_cmd_no_error(
         subtype = check_subtype(node)
         if subtype == NodeSubTypeTG.TREX:
             exec_cmd_no_error(

-                node, "sh -c 'sudo pkill t-rex && sleep 3'",
-                sudo=False, message='pkill t-rex failed')
+                node,
+                u"sh -c "
+                u"\"if pgrep t-rex; then sudo pkill t-rex && sleep 3; fi\"",
+                sudo=False,
+                message=u"pkill t-rex failed"
+            )

 
     def _parse_traffic_results(self, stdout):
         """Parse stdout of scripts into fields of self.
 
     def _parse_traffic_results(self, stdout):
         """Parse stdout of scripts into fields of self.


@@ -399,13 +469,16 @@ class TrafficGenerator(AbstractMeasurer):
         # last line from console output
         line = stdout.splitlines()[-1]
         self._result = line
         # 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)[1]
-        self._sent = self._result.split(', ')[2].split('=', 1)[1]
-        self._loss = self._result.split(', ')[3].split('=', 1)[1]
-        self._latency = []
-        self._latency.append(self._result.split(', ')[4].split('=', 1)[1])
-        self._latency.append(self._result.split(', ')[5].split('=', 1)[1])
+        logger.info(f"TrafficGen result: {self._result}")
+        self._received = self._result.split(u", ")[1].split(u"=", 1)[1]
+        self._sent = self._result.split(u", ")[2].split(u"=", 1)[1]
+        self._loss = self._result.split(u", ")[3].split(u"=", 1)[1]
+        self._approximated_duration = \
+            self._result.split(u", ")[5].split(u"=", 1)[1]
+        self._approximated_rate = self._result.split(u", ")[6].split(u"=", 1)[1]
+        self._latency = list()
+        self._latency.append(self._result.split(u", ")[7].split(u"=", 1)[1])
+        self._latency.append(self._result.split(u", ")[8].split(u"=", 1)[1])

 
     def trex_stl_stop_remote_exec(self, node):
         """Execute script on remote node over ssh to stop running traffic.
 
     def trex_stl_stop_remote_exec(self, node):
         """Execute script on remote node over ssh to stop running traffic.


@@ -417,17 +490,17 @@ class TrafficGenerator(AbstractMeasurer):
         :raises RuntimeError: If stop traffic script fails.
         """
         # No need to check subtype, we know it is TREX.
         :raises RuntimeError: If stop traffic script fails.
         """
         # No need to check subtype, we know it is TREX.

-        x_args = ""
+        command_line = OptionString().add(u"python3")
+        dirname = f"{Constants.REMOTE_FW_DIR}/GPL/tools/trex"
+        command_line.add(f"'{dirname}/trex_stateless_stop.py'")
+        command_line.change_prefix(u"--")

         for index, value in enumerate(self._xstats):
             if value is not None:
         for index, value in enumerate(self._xstats):
             if value is not None:

-                # Nested quoting is fun.
-                value = value.replace("'", "\"")
-                x_args += " --xstat{i}='\"'\"'{v}'\"'\"'".format(
-                    i=index, v=value)
+                value = value.replace(u"'", u"\"")
+                command_line.add_equals(f"xstat{index}", f"'{value}'")

         stdout, _ = exec_cmd_no_error(
         stdout, _ = exec_cmd_no_error(

-            node, "sh -c '{d}/resources/tools/trex/trex_stateless_stop.py{a}'"\
-            .format(d=Constants.REMOTE_FW_DIR, a=x_args),
-            message='TRex stateless runtime error')
+            node, command_line, message=u"TRex stateless runtime error"
+        )

         self._parse_traffic_results(stdout)
 
     def trex_stl_start_remote_exec(
         self._parse_traffic_results(stdout)
 
     def trex_stl_start_remote_exec(


@@ -443,7 +516,7 @@ class TrafficGenerator(AbstractMeasurer):
         :param rate: Traffic rate expressed with units (pps, %)
         :param frame_size: L2 frame size to send (without padding and IPG).
         :param traffic_profile: Module name as a traffic profile identifier.
         :param rate: Traffic rate expressed with units (pps, %)
         :param frame_size: L2 frame size to send (without padding and IPG).
         :param traffic_profile: Module name as a traffic profile identifier.

-            See resources/traffic_profiles/trex for implemented modules.
+            See GPL/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.
         :param async_call: If enabled then don't wait for all incomming trafic.
         :param latency: With latency measurement.
         :param warmup_time: Warmup time period.


@@ -468,39 +541,39 @@ class TrafficGenerator(AbstractMeasurer):
         # No need to check subtype, we know it is TREX.
         reorder = self._ifaces_reordered  # Just to make the next line fit.
         p_0, p_1 = (rx_port, tx_port) if reorder else (tx_port, rx_port)
         # No need to check subtype, we know it is TREX.
         reorder = self._ifaces_reordered  # Just to make the next line fit.
         p_0, p_1 = (rx_port, tx_port) if reorder else (tx_port, rx_port)

-        # Values from Robot can introduce type unicode,
-        # we need to encode them, so that repr() does not lead with 'u'.
-        if isinstance(rate, unicode):
-            rate = rate.encode("utf-8")

         if not isinstance(duration, (float, int)):
             duration = float(duration)
         if not isinstance(warmup_time, (float, int)):
             warmup_time = float(warmup_time)
         if not isinstance(duration, (float, int)):
             duration = float(duration)
         if not isinstance(warmup_time, (float, int)):
             warmup_time = float(warmup_time)

-        command = (
-            "sh -c '{tool}/resources/tools/trex/trex_stateless_profile.py"
-            " --profile {prof}/resources/traffic_profiles/trex/{traffic}.py"
-            " --duration {duration!r} --frame_size {frame_size} --rate {rate!r}"
-            " --warmup_time {warmup!r} --port_0 {p_0} --port_1 {p_1}"
-            " --traffic_directions {dirs}").format(
-                tool=Constants.REMOTE_FW_DIR, prof=Constants.REMOTE_FW_DIR,
-                traffic=traffic_profile, duration=duration,
-                frame_size=frame_size, rate=rate, warmup=warmup_time, p_0=p_0,
-                p_1=p_1, dirs=traffic_directions)
-        if async_call:
-            command += " --async_start"
-        if latency:
-            command += " --latency"
-        command += "'"
+
+        command_line = OptionString().add(u"python3")
+        dirname = f"{Constants.REMOTE_FW_DIR}/GPL/tools/trex"
+        command_line.add(f"'{dirname}/trex_stateless_profile.py'")
+        command_line.change_prefix(u"--")
+        dirname = f"{Constants.REMOTE_FW_DIR}/GPL/traffic_profiles/trex"
+        quoted_path = f"'{dirname}/{traffic_profile}.py'"
+        command_line.add_with_value(u"profile", quoted_path)
+        command_line.add_with_value(u"duration", f"{duration!r}")
+        command_line.add_with_value(u"frame_size", frame_size)
+        command_line.add_with_value(u"rate", f"{rate!r}")
+        command_line.add_with_value(u"warmup_time", f"{warmup_time!r}")
+        command_line.add_with_value(u"port_0", p_0)
+        command_line.add_with_value(u"port_1", p_1)
+        command_line.add_with_value(u"traffic_directions", traffic_directions)
+        command_line.add_if(u"async_start", async_call)
+        command_line.add_if(u"latency", latency)
+        command_line.add_if(u"force", Constants.TREX_SEND_FORCE)

 
         stdout, _ = exec_cmd_no_error(
 
         stdout, _ = exec_cmd_no_error(

-            self._node, command, timeout=float(duration) + 60,
-            message='TRex stateless runtime error')
+            self._node, command_line, timeout=float(duration) + 60,
+            message=u"TRex stateless runtime error"
+        )

 
         self.traffic_directions = traffic_directions
         if async_call:
 
         self.traffic_directions = traffic_directions
         if async_call:

-            #no result
+            # no result

             self._start_time = time.time()
             self._start_time = time.time()

-            self._rate = float(rate[:-3]) if "pps" in rate else float(rate)
+            self._rate = float(rate[:-3]) if u"pps" in rate else float(rate)

             self._received = None
             self._sent = None
             self._loss = None
             self._received = None
             self._sent = None
             self._loss = None


@@ -508,7 +581,7 @@ class TrafficGenerator(AbstractMeasurer):
             xstats = [None, None]
             index = 0
             for line in stdout.splitlines():
             xstats = [None, None]
             index = 0
             for line in stdout.splitlines():

-                if "Xstats snapshot {i}: ".format(i=index) in line:
+                if f"Xstats snapshot {index}: " in line:

                     xstats[index] = line[19:]
                     index += 1
                 if index == 2:
                     xstats[index] = line[19:]
                     index += 1
                 if index == 2:


@@ -560,7 +633,7 @@ class TrafficGenerator(AbstractMeasurer):
         :param rate: Offered load per interface (e.g. 1%, 3gbps, 4mpps, ...).
         :param frame_size: Frame size (L2) in Bytes.
         :param traffic_profile: Module name as a traffic profile identifier.
         :param rate: Offered load per interface (e.g. 1%, 3gbps, 4mpps, ...).
         :param frame_size: Frame size (L2) in Bytes.
         :param traffic_profile: Module name as a traffic profile identifier.

-            See resources/traffic_profiles/trex for implemented modules.
+            See GPL/traffic_profiles/trex for implemented modules.

         :param warmup_time: Warmup phase in seconds.
         :param async_call: Async mode.
         :param latency: With latency measurement.
         :param warmup_time: Warmup phase in seconds.
         :param async_call: Async mode.
         :param latency: With latency measurement.


@@ -590,7 +663,8 @@ class TrafficGenerator(AbstractMeasurer):
         if subtype == NodeSubTypeTG.TREX:
             self.trex_stl_start_remote_exec(
                 duration, rate, frame_size, traffic_profile, async_call,
         if subtype == NodeSubTypeTG.TREX:
             self.trex_stl_start_remote_exec(
                 duration, rate, frame_size, traffic_profile, async_call,

-                latency, warmup_time, traffic_directions, tx_port, rx_port)
+                latency, warmup_time, traffic_directions, tx_port, rx_port
+            )

 
         return self._result
 
 
         return self._result
 


@@ -601,9 +675,9 @@ class TrafficGenerator(AbstractMeasurer):
         :raises Exception: If loss occured.
         """
         if self._loss is None:
         :raises Exception: If loss occured.
         """
         if self._loss is None:

-            raise RuntimeError('The traffic generation has not been issued')
-        if self._loss != '0':
-            raise RuntimeError('Traffic loss occurred: {0}'.format(self._loss))
+            raise RuntimeError(u"The traffic generation has not been issued")
+        if self._loss != u"0":
+            raise RuntimeError(f"Traffic loss occurred: {self._loss}")

 
     def fail_if_no_traffic_forwarded(self):
         """Fail if no traffic forwarded.
 
     def fail_if_no_traffic_forwarded(self):
         """Fail if no traffic forwarded.


@@ -612,12 +686,12 @@ class TrafficGenerator(AbstractMeasurer):
         :raises Exception: If no traffic forwarded.
         """
         if self._received is None:
         :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')
+            raise RuntimeError(u"The traffic generation has not been issued")
+        if self._received == u"0":
+            raise RuntimeError(u"No traffic forwarded")

 
 

-    def partial_traffic_loss_accepted(self, loss_acceptance,
-                                      loss_acceptance_type):
+    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.
         """Fail if loss is higher then accepted in traffic run.
 
         :param loss_acceptance: Permitted drop ratio or frames count.


@@ -628,38 +702,43 @@ class TrafficGenerator(AbstractMeasurer):
         :raises Exception: If loss is above acceptance criteria.
         """
         if self._loss is None:
         :raises Exception: If loss is above acceptance criteria.
         """
         if self._loss is None:

-            raise Exception('The traffic generation has not been issued')
+            raise Exception(u"The traffic generation has not been issued")

 
 

-        if loss_acceptance_type == 'percentage':
+        if loss_acceptance_type == u"percentage":

             loss = (float(self._loss) / float(self._sent)) * 100
             loss = (float(self._loss) / float(self._sent)) * 100

-        elif loss_acceptance_type == 'frames':
+        elif loss_acceptance_type == u"frames":

             loss = float(self._loss)
         else:
             loss = float(self._loss)
         else:

-            raise Exception('Loss acceptance type not supported')
+            raise Exception(u"Loss acceptance type not supported")

 
         if loss > float(loss_acceptance):
 
         if loss > float(loss_acceptance):

-            raise Exception("Traffic loss {} above loss acceptance: {}".format(
-                loss, loss_acceptance))
+            raise Exception(
+                f"Traffic loss {loss} above loss acceptance: {loss_acceptance}"
+            )

 
 

-    def set_rate_provider_defaults(self, frame_size, traffic_profile,
-                                   warmup_time=0.0, traffic_directions=2):
+    def set_rate_provider_defaults(
+            self, frame_size, traffic_profile, warmup_time=0.0,
+            traffic_directions=2, negative_loss=True):

         """Store values accessed by measure().
 
         :param frame_size: Frame size identifier or value [B].
         :param traffic_profile: Module name as a traffic profile identifier.
         """Store values accessed by measure().
 
         :param frame_size: Frame size identifier or value [B].
         :param traffic_profile: Module name as a traffic profile identifier.

-            See resources/traffic_profiles/trex for implemented modules.
+            See GPL/traffic_profiles/trex for implemented modules.

         :param warmup_time: Traffic duration before measurement starts [s].
         :param traffic_directions: Traffic is bi- (2) or uni- (1) directional.
             Default: 2
         :param warmup_time: Traffic duration before measurement starts [s].
         :param traffic_directions: Traffic is bi- (2) or uni- (1) directional.
             Default: 2

+        :param negative_loss: If false, negative loss is reported as zero loss.

         :type frame_size: str or int
         :type traffic_profile: str
         :type warmup_time: float
         :type traffic_directions: int
         :type frame_size: str or int
         :type traffic_profile: str
         :type warmup_time: float
         :type traffic_directions: int

+        :type negative_loss: bool

         """
         self.frame_size = frame_size
         self.traffic_profile = str(traffic_profile)
         self.warmup_time = float(warmup_time)
         self.traffic_directions = traffic_directions
         """
         self.frame_size = frame_size
         self.traffic_profile = str(traffic_profile)
         self.warmup_time = float(warmup_time)
         self.traffic_directions = traffic_directions

+        self.negative_loss = negative_loss

 
     def get_measurement_result(self, duration=None, transmit_rate=None):
         """Return the result of last measurement as ReceiveRateMeasurement.
 
     def get_measurement_result(self, duration=None, transmit_rate=None):
         """Return the result of last measurement as ReceiveRateMeasurement.


@@ -685,9 +764,13 @@ class TrafficGenerator(AbstractMeasurer):
             transmit_rate = self._rate * self.traffic_directions
         transmit_count = int(self.get_sent())
         loss_count = int(self.get_loss())
             transmit_rate = self._rate * self.traffic_directions
         transmit_count = int(self.get_sent())
         loss_count = int(self.get_loss())

+        if loss_count < 0 and not self.negative_loss:
+            loss_count = 0

         measurement = ReceiveRateMeasurement(
         measurement = ReceiveRateMeasurement(

-            duration, transmit_rate, transmit_count, loss_count)
+            duration, transmit_rate, transmit_count, loss_count
+        )

         measurement.latency = self.get_latency_int()
         measurement.latency = self.get_latency_int()

+        measurement.approximated_rate = self.get_approximated_rate()

         return measurement
 
     def measure(self, duration, transmit_rate):
         return measurement
 
     def measure(self, duration, transmit_rate):


@@ -709,15 +792,16 @@ class TrafficGenerator(AbstractMeasurer):
         transmit_rate = float(transmit_rate)
         # TG needs target Tr per stream, but reports aggregate Tx and Dx.
         unit_rate_int = transmit_rate / float(self.traffic_directions)
         transmit_rate = float(transmit_rate)
         # TG needs target Tr per stream, but reports aggregate Tx and Dx.
         unit_rate_int = transmit_rate / float(self.traffic_directions)

-        unit_rate_str = str(unit_rate_int) + "pps"
+        unit_rate_str = str(unit_rate_int) + u"pps"

         self.send_traffic_on_tg(
             duration, unit_rate_str, self.frame_size, self.traffic_profile,
             warmup_time=self.warmup_time, latency=True,
         self.send_traffic_on_tg(
             duration, unit_rate_str, self.frame_size, self.traffic_profile,
             warmup_time=self.warmup_time, latency=True,

-            traffic_directions=self.traffic_directions)
+            traffic_directions=self.traffic_directions
+        )

         return self.get_measurement_result(duration, transmit_rate)
 
 
         return self.get_measurement_result(duration, transmit_rate)
 
 

-class OptimizedSearch(object):
+class OptimizedSearch:

     """Class to be imported as Robot Library, containing search keywords.
 
     Aside of setting up measurer and forwarding arguments,
     """Class to be imported as Robot Library, containing search keywords.
 
     Aside of setting up measurer and forwarding arguments,


@@ -735,7 +819,7 @@ class OptimizedSearch(object):
 
         :param frame_size: Frame size identifier or value [B].
         :param traffic_profile: Module name as a traffic profile identifier.
 
         :param frame_size: Frame size identifier or value [B].
         :param traffic_profile: Module name as a traffic profile identifier.

-            See resources/traffic_profiles/trex for implemented modules.
+            See GPL/traffic_profiles/trex for implemented modules.

         :param minimum_transmit_rate: Minimal uni-directional
             target transmit rate [pps].
         :param maximum_transmit_rate: Maximal uni-directional
         :param minimum_transmit_rate: Minimal uni-directional
             target transmit rate [pps].
         :param maximum_transmit_rate: Maximal uni-directional


@@ -777,7 +861,8 @@ class OptimizedSearch(object):
         # we need instance of TrafficGenerator instantiated by Robot Framework
         # to be able to use trex_stl-*()
         tg_instance = BuiltIn().get_library_instance(
         # 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')
+            u"resources.libraries.python.TrafficGenerator"
+        )

         tg_instance.set_rate_provider_defaults(
             frame_size, traffic_profile, traffic_directions=traffic_directions)
         algorithm = MultipleLossRatioSearch(
         tg_instance.set_rate_provider_defaults(
             frame_size, traffic_profile, traffic_directions=traffic_directions)
         algorithm = MultipleLossRatioSearch(


@@ -785,9 +870,11 @@ class OptimizedSearch(object):
             final_relative_width=final_relative_width,
             number_of_intermediate_phases=number_of_intermediate_phases,
             initial_trial_duration=initial_trial_duration, timeout=timeout,
             final_relative_width=final_relative_width,
             number_of_intermediate_phases=number_of_intermediate_phases,
             initial_trial_duration=initial_trial_duration, timeout=timeout,

-            doublings=doublings)
+            doublings=doublings
+        )

         result = algorithm.narrow_down_ndr_and_pdr(
         result = algorithm.narrow_down_ndr_and_pdr(

-            minimum_transmit_rate, maximum_transmit_rate, packet_loss_ratio)
+            minimum_transmit_rate, maximum_transmit_rate, packet_loss_ratio
+        )

         return result
 
     @staticmethod
         return result
 
     @staticmethod


@@ -800,7 +887,7 @@ class OptimizedSearch(object):
 
         :param frame_size: Frame size identifier or value [B].
         :param traffic_profile: Module name as a traffic profile identifier.
 
         :param frame_size: Frame size identifier or value [B].
         :param traffic_profile: Module name as a traffic profile identifier.

-            See resources/traffic_profiles/trex for implemented modules.
+            See GPL/traffic_profiles/trex for implemented modules.

         :param minimum_transmit_rate: Minimal uni-directional
             target transmit rate [pps].
         :param maximum_transmit_rate: Maximal uni-directional
         :param minimum_transmit_rate: Minimal uni-directional
             target transmit rate [pps].
         :param maximum_transmit_rate: Maximal uni-directional


@@ -814,6 +901,7 @@ class OptimizedSearch(object):
             This is needed because initial "search" phase of integrator
             takes significant time even without any trial results.
         :param timeout: The search will stop after this overall time [s].
             This is needed because initial "search" phase of integrator
             takes significant time even without any trial results.
         :param timeout: The search will stop after this overall time [s].

+        :param trace_enabled: True if trace enabled else False.

         :param traffic_directions: Traffic is bi- (2) or uni- (1) directional.
             Default: 2
         :type frame_size: str or int
         :param traffic_directions: Traffic is bi- (2) or uni- (1) directional.
             Default: 2
         :type frame_size: str or int


@@ -823,6 +911,7 @@ class OptimizedSearch(object):
         :type plr_target: float
         :type initial_count: int
         :type timeout: float
         :type plr_target: float
         :type initial_count: int
         :type timeout: float

+        :type trace_enabled: bool

         :type traffic_directions: int
         :returns: Average and stdev of estimated aggregate rate giving PLR.
         :rtype: 2-tuple of float
         :type traffic_directions: int
         :returns: Average and stdev of estimated aggregate rate giving PLR.
         :rtype: 2-tuple of float


@@ -830,13 +919,16 @@ class OptimizedSearch(object):
         minimum_transmit_rate *= traffic_directions
         maximum_transmit_rate *= traffic_directions
         tg_instance = BuiltIn().get_library_instance(
         minimum_transmit_rate *= traffic_directions
         maximum_transmit_rate *= traffic_directions
         tg_instance = BuiltIn().get_library_instance(

-            'resources.libraries.python.TrafficGenerator')
+            u"resources.libraries.python.TrafficGenerator"
+        )

         tg_instance.set_rate_provider_defaults(
         tg_instance.set_rate_provider_defaults(

-            frame_size, traffic_profile, traffic_directions=traffic_directions)
+            frame_size, traffic_profile, traffic_directions=traffic_directions,
+            negative_loss=False)

         algorithm = PLRsearch(
             measurer=tg_instance, trial_duration_per_trial=tdpt,
             packet_loss_ratio_target=plr_target,
             trial_number_offset=initial_count, timeout=timeout,
         algorithm = PLRsearch(
             measurer=tg_instance, trial_duration_per_trial=tdpt,
             packet_loss_ratio_target=plr_target,
             trial_number_offset=initial_count, timeout=timeout,

-            trace_enabled=trace_enabled)
+            trace_enabled=trace_enabled
+        )

         result = algorithm.search(minimum_transmit_rate, maximum_transmit_rate)
         return result
         result = algorithm.search(minimum_transmit_rate, maximum_transmit_rate)
         return result