AAI Performance Hosts - Peak Throughput Evaluation Experiments

We have performed several experiments to evaluate the peak throughput performance of DEC AXP-3000/700 workstations. These machines are being deployed in the AAI testbed network for wide area network (WAN) experimentation. These initial experiments were performed in the TISL laboratory in order to better understand the performance envelope of these machines and provide a baseline for the WAN experiments.

Several configurations were studied:

• firewall configuration
• router configuration
• dual transmit configuration
• dual receive configuration
• single pair baseline configuration

In each case, the performance was evaluated for various combinations of TCP window size, TCP/IP MTU size, and application buffer size.

Some common parameters in these tests:

• Hosts: Digital Alpha AXP-3000/700s
• Operating System: Digital Unix 3.2D
• Interfaces: DEC ATMworks-750 ATM/SONET OC-3c
• Drivers: DEC Systems Research Center ATM OTTO device drivers
• Links: SONET/ATM OC-3c (TCP maximum = 134 Mbit/sec)
• Round-trip Times: less than 1 ms

The results are summarized below, with additional details on the referenced pages.

Firewall Configuration

Peak Performance: 110.62 Mbit/sec (536870912 bytes in 37.03 seconds)
Firewall: 536870912 bytes in 37.03 real seconds = 110.62 Mbit/sec
Maximum TCP Window: 524288
Application Buffer Size: 131072
IP MTU: 9180
Evaluation Tool: ttcp
Proxy: plug-gw from TIS fwtkV1.3
Detailed Results: here

Router Configuration

Peak Performance: 128.05 Mbit/sec (536870912 bytes in 31.99 seconds)
Maximum TCP Window: 524288
Application Buffer Size: 131072
IP MTU: 9180
Evaluation Tool: NetSpec
Detailed Results: here

Dual Transmit Configuration

Peak Performance: 232.274 Mbit/sec (aggregate)
Maximum TCP Window: 524288
Application Buffer Size: 131072
IP MTU: 9180
Evaluation Tool: NetSpec
Detailed Results: here

Dual Receive Configuration

Peak Performance: 204.806 Mbit/sec (aggregate)
Maximum TCP Window: 524288
Application Buffer Size: 131072
IP MTU: 9180
Evaluation Tool: NetSpec
Detailed Results: here

Single Pair Baseline Configuration

Peak Performance: 134.458 Mbit/sec
Maximum TCP Window: 65536
Application Buffer Size: 4096
IP MTU: 9180

Evaluation Tool: NetSpec
Detailed Results: here

Evaluation Tool: ttcp
Detailed Results: here

Authors: Joseph B. Evans, evans@ittc.ku.edu and Benjamin J. Ewy, bewy@ittc.ku.edu