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 007079f..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:


@@ -18,16 +18,18 @@ 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__ = [u"TGDropRateSearchImpl", u"TrafficGenerator", u"OptimizedSearch"]
 
 
 __all__ = [u"TGDropRateSearchImpl", u"TrafficGenerator", u"OptimizedSearch"]
 


@@ -73,7 +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


@@ -149,6 +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


@@ -157,6 +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?


@@ -202,6 +207,15 @@ 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(
     # TODO: pylint says disable=too-many-locals.
     # A fix is developed in https://gerrit.fd.io/r/c/csit/+/22221
     def initialize_traffic_generator(


@@ -277,6 +291,11 @@ 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
 

+            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')}"
             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')}"


@@ -286,90 +305,124 @@ class TrafficGenerator(AbstractMeasurer):
                     self._node,
                     f"sh -c 'cat << EOF > /etc/trex_cfg.yaml\n"
                     f"- version: 2\n"
                     self._node,
                     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"  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'",
                     f"EOF'",

-                    sudo=True, message=u"TRex config generation error"
+                    sudo=True, message=u"TRex config generation!"

                 )
             elif osi_layer == u"L7":
                 exec_cmd_no_error(
                     self._node,
                     f"sh -c 'cat << EOF > /etc/trex_cfg.yaml\n"
                     f"- version: 2\n"
                 )
             elif osi_layer == u"L7":
                 exec_cmd_no_error(
                     self._node,
                     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"  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'",
                     f"EOF'",

-                    sudo=True, message=u"TRex config generation error"
+                    sudo=True, message=u"TRex config generation!"

                 )
             else:
                 )
             else:

-                raise ValueError(u"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 = u"sh -c \"pgrep t-rex && pkill t-rex && sleep 3 || true\""
-            exec_cmd_no_error(
-                self._node, cmd, sudo=True, message=u"Kill TRex failed!"
-            )
-
-            # Configure TRex.
-            ports = ''
-            for port in self._node[u"interfaces"].values():
-                ports += f" {port.get(u'pci_address')}"
-
-            cmd = f"sh -c \"cd {Constants.TREX_INSTALL_DIR}/scripts/ && " \
-                f"./dpdk_nic_bind.py -u {ports} || true\""
-            exec_cmd_no_error(
-                self._node, cmd, sudo=True,
-                message=u"Unbind PCI ports from driver failed!"
-            )
-
-            # Start TRex.
-            cmd = f"sh -c \"cd {Constants.TREX_INSTALL_DIR}/scripts/ && " \
-                f"nohup ./t-rex-64 " \
-                f"--hdrh{u' --astf' if osi_layer == u'L7' else u''} " \
-                f"--prefix $(hostname) -i -c 7 > /tmp/trex.log 2>&1 &\" > " \
-                f"/dev/null"
-            try:
-                exec_cmd_no_error(self._node, cmd, sudo=True)
-            except RuntimeError:
-                cmd = u"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=u"Get TRex logs failed!"
+                    tg_node, cmd, sudo=True, message=u"Kill TRex failed!"

                 )
                 )

-                raise RuntimeError(u"Start TRex failed!")

 
 

-            # Test if TRex starts successfuly.
-            cmd = f"sh -c \"{Constants.REMOTE_FW_DIR}/resources/tools/trex/" \
-                f"trex_server_info.py\""
-            try:
+                # Configure TRex.
+                ports = ''
+                for port in tg_node[u"interfaces"].values():
+                    ports += f" {port.get(u'pci_address')}"
+
+                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=u"Test TRex failed!",
-                    retries=20
+                    tg_node, cmd, sudo=True,
+                    message=u"Unbind PCI ports from driver failed!"

                 )
                 )

-            except RuntimeError:
-                continue
-            return
-        # After max retries TRex is still not responding to API critical error
-        # occurred.
-        raise RuntimeError(u"Start TRex failed after multiple retries!")
+
+                # 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):


@@ -381,9 +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, u"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


@@ -399,8 +450,11 @@ 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, u"sh -c \"sudo pkill t-rex && sleep 3\"",
-                sudo=False, message=u"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):
             )
 
     def _parse_traffic_results(self, stdout):


@@ -419,9 +473,12 @@ class TrafficGenerator(AbstractMeasurer):
         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._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 = list()

-        self._latency.append(self._result.split(u", ")[4].split(u"=", 1)[1])
-        self._latency.append(self._result.split(u", ")[5].split(u"=", 1)[1])
+        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.


@@ -433,16 +490,16 @@ 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 = u""
+        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(u"'", u"\"")
                 value = value.replace(u"'", u"\"")

-                x_args += f" --xstat{index}='\"'\"'{value}'\"'\"'"
+                command_line.add_equals(f"xstat{index}", f"'{value}'")

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

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

         )
         self._parse_traffic_results(stdout)
 
         )
         self._parse_traffic_results(stdout)
 


@@ -459,7 +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.


@@ -484,28 +541,31 @@ 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)

-

         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 = f"sh -c \"" \
-            f"{Constants.REMOTE_FW_DIR}/resources/tools/trex/" \
-            f"trex_stateless_profile.py" \
-            f" --profile {Constants.REMOTE_FW_DIR}/resources/" \
-            f"traffic_profiles/trex/{traffic_profile}.py" \
-            f" --duration {duration!r} --frame_size {frame_size} " \
-            f"--rate {rate!r} --warmup_time {warmup_time!r} " \
-            f"--port_0 {p_0} --port_1 {p_1}" \
-            f" --traffic_directions {traffic_directions}"
-        if async_call:
-            command += u" --async_start"
-        if latency:
-            command += u" --latency"
-        command += u"\""
+
+        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,
+            self._node, command_line, timeout=float(duration) + 60,

             message=u"TRex stateless runtime error"
         )
 
             message=u"TRex stateless runtime error"
         )
 


@@ -573,7 +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.


@@ -658,24 +718,27 @@ class TrafficGenerator(AbstractMeasurer):
 
     def set_rate_provider_defaults(
             self, frame_size, traffic_profile, warmup_time=0.0,
 
     def set_rate_provider_defaults(
             self, frame_size, traffic_profile, warmup_time=0.0,

-            traffic_directions=2):
+            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.


@@ -701,10 +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(
             duration, transmit_rate, transmit_count, loss_count
         )
         measurement.latency = self.get_latency_int()
         measurement = ReceiveRateMeasurement(
             duration, transmit_rate, transmit_count, loss_count
         )
         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):


@@ -753,7 +819,7 @@ class OptimizedSearch:
 
         :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


@@ -821,7 +887,7 @@ class OptimizedSearch:
 
         :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


@@ -856,7 +922,8 @@ class OptimizedSearch:
             u"resources.libraries.python.TrafficGenerator"
         )
         tg_instance.set_rate_provider_defaults(
             u"resources.libraries.python.TrafficGenerator"
         )
         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,
         algorithm = PLRsearch(
             measurer=tg_instance, trial_duration_per_trial=tdpt,
             packet_loss_ratio_target=plr_target,