Make TRex IMIX traffic mode configurable

Enable TRex IMIX generation using two modes:
  - Distribution in packages.
  - Distribution in byes.

The default one will be distribution in packages, like the default
one in IxNetwork.

JIRA: YARDSTICK-1397

Change-Id: I86b2527968496218b0515349fc0a2680a84261e5
Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>

3 files changed, 60 insertions, 9 deletions

diff --git a/yardstick/common/constants.py b/yardstick/common/constants.py
index 3d775d48e..03733b6da 100644
--- a/yardstick/common/constants.py
+++ b/yardstick/common/constants.py
@@ -176,3 +176,7 @@ SCOPE_CLUSTER = 'Cluster'
 # VNF definition
 SSH_PORT = 22
 LUA_PORT = 22022
+
+# IMIX mode
+DISTRIBUTION_IN_PACKETS = 'mode_DIP'
+DISTRIBUTION_IN_BYTES = 'mode_DIB'
diff --git a/yardstick/network_services/traffic_profile/rfc2544.py b/yardstick/network_services/traffic_profile/rfc2544.py
index 987029373..4b339c2ed 100644
--- a/yardstick/network_services/traffic_profile/rfc2544.py
+++ b/yardstick/network_services/traffic_profile/rfc2544.py
@@ -19,6 +19,7 @@ from trex_stl_lib import trex_stl_client
 from trex_stl_lib import trex_stl_packet_builder_scapy
 from trex_stl_lib import trex_stl_streams
 
+from yardstick.common import constants
 from yardstick.network_services.traffic_profile import trex_traffic_profile
 
 
@@ -140,7 +141,8 @@ class RFC2544Profile(trex_traffic_profile.TrexProfile):
             streams.extend(_streams)
         return trex_stl_streams.STLProfile(streams)
 
-    def _create_imix_data(self, imix):
+    def _create_imix_data(self, imix,
+                          weight_mode=constants.DISTRIBUTION_IN_PACKETS):
         """Generate the IMIX distribution for a STL profile
 
         The input information is the framesize dictionary in a test case
@@ -159,6 +161,20 @@ class RFC2544Profile(trex_traffic_profile.TrexProfile):
         E.g.:
           imix_count = {64: 25, 128: 75}
 
+        The weight mode is described in [1]. There are two ways to describe the
+        weight of the packets:
+          - Distribution in packets: the weight defines the percentage of
+            packets sent per packet size. IXIA uses this definition.
+          - Distribution in bytes: the weight defines the percentage of bytes
+            sent per packet size.
+
+        Packet size  # packets  D. in packets  Bytes  D. in bytes
+        40           7          58.33%         280    7%
+        576          4          33.33%         2304   56%
+        1500         1          8.33%          1500   37%
+
+        [1] https://en.wikipedia.org/wiki/Internet_Mix
+
         :param imix: (dict) IMIX size and weight
         """
         imix_count = {}
@@ -173,8 +189,16 @@ class RFC2544Profile(trex_traffic_profile.TrexProfile):
             imix_sum = 100
 
         weight_normalize = float(imix_sum) / 100
-        return {size: float(weight) / weight_normalize
-                for size, weight in imix_count.items()}
+        imix_dip = {size: float(weight) / weight_normalize
+                    for size, weight in imix_count.items()}
+
+        if weight_mode == constants.DISTRIBUTION_IN_BYTES:
+            return imix_dip
+
+        byte_total = sum([int(size) * weight
+                          for size, weight in imix_dip.items()])
+        return {size: (int(size) * weight) / byte_total
+                for size, weight in imix_dip.items()}
 
     def _create_vm(self, packet_definition):
         """Create the STL Raw instructions"""
diff --git a/yardstick/tests/unit/network_services/traffic_profile/test_rfc2544.py b/yardstick/tests/unit/network_services/traffic_profile/test_rfc2544.py
index cfeebaa3a..4c546d7ef 100644
--- a/yardstick/tests/unit/network_services/traffic_profile/test_rfc2544.py
+++ b/yardstick/tests/unit/network_services/traffic_profile/test_rfc2544.py
@@ -20,6 +20,7 @@ from trex_stl_lib import trex_stl_client
 from trex_stl_lib import trex_stl_packet_builder_scapy
 from trex_stl_lib import trex_stl_streams
 
+from yardstick.common import constants
 from yardstick.network_services.traffic_profile import rfc2544
 from yardstick.tests.unit import base
 
@@ -140,16 +141,38 @@ class TestRFC2544Profile(base.BaseUnitTestCase):
                                                     port_pg_id, True)
         mock_stl_profile.assert_called_once_with(['stream1'])
 
-    def test__create_imix_data(self):
+    def test__create_imix_data_mode_DIB(self):
         rfc2544_profile = rfc2544.RFC2544Profile(self.TRAFFIC_PROFILE)
         data = {'64B': 50, '128B': 50}
-        self.assertEqual({'64': 50.0, '128': 50.0},
-                         rfc2544_profile._create_imix_data(data))
+        self.assertEqual(
+            {'64': 50.0, '128': 50.0},
+            rfc2544_profile._create_imix_data(
+                data, weight_mode=constants.DISTRIBUTION_IN_BYTES))
         data = {'64B': 1, '128b': 3}
-        self.assertEqual({'64': 25.0, '128': 75.0},
-                         rfc2544_profile._create_imix_data(data))
+        self.assertEqual(
+            {'64': 25.0, '128': 75.0},
+            rfc2544_profile._create_imix_data(
+                data, weight_mode=constants.DISTRIBUTION_IN_BYTES))
         data = {}
-        self.assertEqual({}, rfc2544_profile._create_imix_data(data))
+        self.assertEqual(
+            {},
+            rfc2544_profile._create_imix_data(
+                data, weight_mode=constants.DISTRIBUTION_IN_BYTES))
+
+    def test__create_imix_data_mode_DIP(self):
+        rfc2544_profile = rfc2544.RFC2544Profile(self.TRAFFIC_PROFILE)
+        data = {'64B': 25, '128B': 25, '512B': 25, '1518B': 25}
+        byte_total = 64 * 25 + 128 * 25 + 512 * 25 + 1518 * 25
+        self.assertEqual(
+            {'64': 64 * 25.0 / byte_total, '128': 128 * 25.0 / byte_total,
+             '512': 512 * 25.0 / byte_total, '1518': 1518 * 25.0 / byte_total},
+            rfc2544_profile._create_imix_data(
+                data, weight_mode=constants.DISTRIBUTION_IN_PACKETS))
+        data = {}
+        self.assertEqual(
+            {},
+            rfc2544_profile._create_imix_data(
+                data, weight_mode=constants.DISTRIBUTION_IN_PACKETS))
 
     def test__create_vm(self):
         packet = {'outer_l2': 'l2_definition'}