Figure 3a (Page 7) is used to show the the affect of network interference in network switches and the extent to which QJump can fix it. It also gives an indication of the limits of QJump's performance. It shows that prioritization inside of switches does not resolve all interference.

WARNING This experiment requires use of an Endace DAG 9.2x2 or similar capture card and two passive optical taps for high fidelty network capture.

Figure 3a

Software Required

In addition to these general software requirements, we also used:

Physical Configuration

The basic physical network configuration is described here. In this experiment the following configuration was used:

Sofware Configuration

Iperf servers and clients were configured respectively:

iperf -s -i1 -P 3

iperf -c 10.10.0.XXX -t 99999 -i 1 -P 3

Ping was configured as follows:

sudo ping -i 0.01

When QJump was enabled, it was configured as follows

timeq=15 bytesq=1550 p7rate=300 p6rate=0 p5rate=0 p4rate=150 p3rate=30 p2rate=15 p1rate=5 p0rate=1

To run ping with QJump enabled, it was run with our application utility:

./ -p 7 -c "sudo ping -i 0.01"

The DAG capture tool was configured as follows:

sudo ./bin/dag_capture -s 10000 -t 0

Raw Data

Our original unprocessed datasets can be found here (1.92MB). There are 30 files in the archive. Each file contains ERF records from the DAG capture. The files come in pairs: each pair contains a 201 and 205 file which represents the sending and recieving sides. The file names are of the form:

Processing and plotting the results

The processing and plotting scripts can be found here. The processing scripts rely on the presence of dag_analyse and dag_join tools in order to process the binary files. Instructions for obtaining and building these tools can be found here .

./ ../data/ping_dag/ping201205_ 0 ../qjump-camio-tools/

Which will produde the file out_ping201205_0.lats. This can then be plotted along with the other files with:

python ../data/ping_dag/out_ping201205_0.lats ../data/ping_dag/out_ping201205_iperf301205_iperfBS207_0.lats iperf ping ../data/ping_dag/out_ping201205_iperf301205_iperfBS207_TCP7_0.lats qjump figure3a