LoBoS 4

With the combination of LoBoS 3 and Biowulf, there was a need to upgrade the LoBoS 2 cluster which was, by 2001, showing its age. The new cluster was designed with 70 compute nodes. In a departure from previous clusters, these nodes would use AMD CPUs instead of Intel chips. LoBoS 4 also saw the deployment of Myrinet, a proprietary high-bandwidth, low-latency data link layer network technology in the LoBoS cluster.

Unfortunately, these nodes had reliability problems. In particular, the motherboards proved problematic, requiring frequent reboots, which put undue stress on the power supplies, which in turn failed at a much higher than expected rate. In addition there were problems with ensuring sufficient power and cooling for the nodes, although these issues were finally resolved. However, because of the component failures, the LoBoS 4 nodes were returned to their vendor in exchange for a discount on some of the nodes that would eventually become LoBoS 5.

Equipment	Notes
70 Compute Nodes	Tyan MPX motherboard Dual AMD Athlon MP 2000+ with a 256 KB L2 cache 2048 MB PC-2100 DDR SDRAM with 2048 MB of swap space 266 MHz system bus 20 GB 7200 RPM EIDE hard drive 3Com 10/100 network interface card Myrinet C-Card fiber-optic network interface card
4 master nodes	Supermicro motherboard Dual 450 MHz Intel Pentium II CPUs with 512 KB L2 cache 9 GB EIDE hard drive 1.2 TB RAID5 storage with RAIDZONE SmartCans
Myrinet switching hardware	M3-E128 9U switch enclosure 8 M3-SW16 line cards

A Myrinet M3-SW16 line card.