Test

Introduction

This page provides the setting of the performed test and some results.

Test setting

All the test are performed with ns-3 in optimized mode. Netmap is used in emulated mode (with the default device driver) to emulate an ethernet device. The following netmap parameters in sys/module/netmap/parameters are to the values

• generic_txqdisc = 0
• generic_ringsize = 256

Also, the test are performed on a back-to-back ethernet link with bandwidth of 100 Mbps. We can set the bandwidth to 100 Mbps by ethtool (if supported by device) with

• sudo ethtool -s interface speed 100 duplex full

Finally, the emulated interface must be in promisc mode. We can set the promisc mode with

• sudo ip link set interface promisc on

Test results

For the following test we use the fd-netmap-emu-ping example in the fd-net-device module. The example ping a real host connected back-to-back while generating UDP traffic load. The example output shows the ping response, the sampled backlog of packets in the traffic-control queue disc and the inflight in the netmap tx ring.

Flow control

The user can run the example (after a proper configuration of the interface name, the network address, mask and gateway) with

• ./waf --run 'src/fd-net-device/examples/fd-netmap-emu-ping'

The example output shows a growth in the inflight in the netmap tx ring (up to the capacity of the tx ring) and the presence of packets in the traffic-control queue disc of ns-3.

BQL

The user can run the example (after a proper configuration of the interface name, the network address, mask and gateway) with

• ./waf --run 'src/fd-net-device/examples/fd-netmap-emu-ping --bql=true'

The example output shows the inflight in the netmap tx ring under the tx ring capacity and almost constant and shows the presence of packets in the traffic-control queue disc of ns-3.