The Beowulf Cluster

• The idea of the Beowulf cluster project was to achieve supercomputer processing power using off-the-shelf commodity machines. One of the earliest Beowulf clusters contained sixteen 100 MHz DX4 processors that were connected using 10 Mbps Ethernet. The second Beowulf cluster, built in 1995, used 100 MHz Pentium processors connected by 100 Mbps Ethernet.
• The third generation of Beowulf clusters was built by different research laboratories. JPL and Los Alamos National Laboratory each built a 16-processor machine incorporating Pentium Pro processors. These machines were combined to run a large N-body problem, which won the 1997 Gordon Bell Prize for high performance.
• The communication between processors in Beowulf has been done through TCP/IP over the Ethernet internal to the cluster. Multiple Ethernets were also used to satisfy higher bandwidth requirements. Channel bonding is a technique to connect multiple Ethernets in order to distribute the communication traffic. Channel bonding was able to increase the sustained network throughput by 75% when dual networks were used.
• Two of the early successful Beowulf clusters are Loki and Avalon. In 1997, Loki was built using 16 Pentium Pro Processors connected using Fast Ethernet switches. It achieved 1.2 Gflops. In 1998, the Avalon was built using one hundred and forty 533 MHz Alpha Microprocessors connected. Avalon achieved 47.7 Gflops.