UDP send rates for 82byte packets (128byte ethernet)

Purpose

By determining the transfer rates out of udp packets generated by udpmon (v3) for various interpacket times, we can determine at which rate we should send packets out of the mb-ng machines so that we can form a direct comparision between the comparision to the Spirent SmartBits machines.

Equipment

The tests were conducted with Boston Dual Xeon machines, running Red Hat Linux 2.4.9 unmodified. The kernel module for the ethernet device was: ...

Method

As results of SmartMetric SmartFlow are already available, we wish to determine the performance profile of the mbng boston machines using similar configurations.

128byte ethernet frame were currently tested using smartbits on the setup below:

As we are only interested in the raw output of the udp packets, the interpacket_time was varied for the same udp packet size of 90bytes. This value adds up a full ethernet frame size of +18+20 = 128byte frames.

The test was repeated three times from mbng2 eth1 to mbng3 eth1 through the rtr2 bottleneck of 10mbit/sec.

Results

The data files for each test can be found here for test1 test2 test3

There is little variation for relatively longer interpacket times. The main flucuation in the results are when we have small interpacket times as these are more prone to flucuation. Results show that we can achieve 1mbit/sec output with about 700usec interpacket time. Similarly, we get about 10mbit/sec at about 100usec.

Zooming in on the regions we're interested at:

An excel file containing the averages of the throughputs can be found here.

Important interpacket_times for different send_data_rates are shown below:

Wed, 23 July, 2003 13:07