Crunching Numbers, Two Ways

Oil-exploration firm CGG Americas replaced its supercomputers with a cluster of several thousand personal computers linked by specialized networking software. Here’s one view of how the alternatives stack up.

 
Silicon Graphics Origin 3000

Cluster of Dell Computer PCs
ArchitectureSymmetric multiprocessing, where many processors share a single operating system and access each other’s memoryParallel processing, where a computing job is split among many processors that each have their own operating system and memory
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Cost of system$2.9 million$2 million
Number of processors1281,024
Cost per processor$22,656$1,953
System memory256 gigabytesUp to 2 terabytes
PlusesDesigned specifically for scientific applications that do highly complex modeling

All processors can communicate quickly with all other processors, which means certain computing jobs can be done very quickly

Relatively low cost of ownership

Distributed architecture decreases risk that a single processor failure will stop entire job

Power can be added incrementally

Often uses Linux, a hot technology for which skilled workers are readily found

MinusesProcessor failure can halt an entire computing job

Adding power generally adds expense: another $2.9 million machine

Experienced technicians hard to find

Setup and configuration often take several weeks

Overall performance can be negatively affected by speed of the network connecting the processors

Constant monitoring of individual parts is necessary; more parts means more potential points of failure

Large physical space required as cluster grows; additional air conditioning and electric power are sometimes needed