diff options
Diffstat (limited to 'nfvbench/traffic_gen/trex.py')
| -rw-r--r-- | nfvbench/traffic_gen/trex.py | 37 |
1 files changed, 24 insertions, 13 deletions
diff --git a/nfvbench/traffic_gen/trex.py b/nfvbench/traffic_gen/trex.py index 6aec57d..6bb0c34 100644 --- a/nfvbench/traffic_gen/trex.py +++ b/nfvbench/traffic_gen/trex.py @@ -27,6 +27,9 @@ from nfvbench.utils import TimeoutError from traffic_base import AbstractTrafficGenerator from traffic_base import TrafficGeneratorException import traffic_utils as utils +from traffic_utils import IMIX_AVG_L2_FRAME_SIZE +from traffic_utils import IMIX_L2_SIZES +from traffic_utils import IMIX_RATIOS # pylint: disable=import-error from trex_stl_lib.api import CTRexVmInsFixHwCs @@ -245,15 +248,17 @@ class TRex(AbstractTrafficGenerator): results['avg_delay_usec'] = int(average / self.chain_count) def _create_pkt(self, stream_cfg, l2frame_size): + """Create a packet of given size. + + l2frame_size: size of the L2 frame in bytes (including the 32-bit FCS) + """ + # Trex will add the FCS field, so we need to remove 4 bytes from the l2 frame size + frame_size = int(l2frame_size) - 4 + pkt_base = Ether(src=stream_cfg['mac_src'], dst=stream_cfg['mac_dst']) if stream_cfg['vlan_tag'] is not None: - # 50 = 14 (Ethernet II) + 4 (Vlan tag) + 4 (CRC Checksum) + 20 (IPv4) + 8 (UDP) pkt_base /= Dot1Q(vlan=stream_cfg['vlan_tag']) - l2payload_size = int(l2frame_size) - 50 - else: - # 46 = 14 (Ethernet II) + 4 (CRC Checksum) + 20 (IPv4) + 8 (UDP) - l2payload_size = int(l2frame_size) - 46 - payload = 'x' * l2payload_size + udp_args = {} if stream_cfg['udp_src_port']: udp_args['sport'] = int(stream_cfg['udp_src_port']) @@ -301,8 +306,9 @@ class TRex(AbstractTrafficGenerator): l4_offset="UDP", l4_type=CTRexVmInsFixHwCs.L4_TYPE_UDP) ] + pad = max(0, frame_size - len(pkt_base)) * 'x' - return STLPktBuilder(pkt=pkt_base / payload, vm=STLScVmRaw(vm_param)) + return STLPktBuilder(pkt=pkt_base / pad, vm=STLScVmRaw(vm_param)) def generate_streams(self, port, chain_id, stream_cfg, l2frame, latency=True): """Create a list of streams corresponding to a given chain and stream config. @@ -310,15 +316,13 @@ class TRex(AbstractTrafficGenerator): port: port where the streams originate (0 or 1) chain_id: the chain to which the streams are associated to stream_cfg: stream configuration - l2frame: L2 frame size + l2frame: L2 frame size (including 4-byte FCS) or 'IMIX' latency: if True also create a latency stream """ streams = [] pg_id, lat_pg_id = self.get_pg_id(port, chain_id) if l2frame == 'IMIX': - min_size = 64 if stream_cfg['vlan_tag'] is None else 68 - self.adjust_imix_min_size(min_size) - for ratio, l2_frame_size in zip(self.imix_ratios, self.imix_l2_sizes): + for ratio, l2_frame_size in zip(IMIX_RATIOS, IMIX_L2_SIZES): pkt = self._create_pkt(stream_cfg, l2_frame_size) streams.append(STLStream(packet=pkt, flow_stats=STLFlowStats(pg_id=pg_id), @@ -326,13 +330,20 @@ class TRex(AbstractTrafficGenerator): if latency: # for IMIX, the latency packets have the average IMIX packet size - pkt = self._create_pkt(stream_cfg, self.imix_avg_l2_size) + pkt = self._create_pkt(stream_cfg, IMIX_AVG_L2_FRAME_SIZE) else: - pkt = self._create_pkt(stream_cfg, l2frame) + l2frame_size = int(l2frame) + pkt = self._create_pkt(stream_cfg, l2frame_size) streams.append(STLStream(packet=pkt, flow_stats=STLFlowStats(pg_id=pg_id), mode=STLTXCont())) + # for the latency stream, the minimum payload is 16 bytes even in case of vlan tagging + # without vlan, the min l2 frame size is 64 + # with vlan it is 68 + # This only applies to the latency stream + if latency and stream_cfg['vlan_tag'] and l2frame_size < 68: + pkt = self._create_pkt(stream_cfg, 68) if latency: streams.append(STLStream(packet=pkt, |