The Hurricane operating system is a hierarchically clustered operating system implemented on the Hector multiprocessor.
Hierarchical clustering manages the system resources in clusters, using tight coupling within a cluster, and loose coupling across clusters. Distributed systems principles are applied by distributing and replicating system services and data objects to increase locality, increase concurrency, and to avoid centralized bottlenecks, thus making the system scalable. However, tight coupling is used within a cluster, so the system performs well for local interactions. Hierarchical clustering maximizes locality which is key to good performance in large systems, and systems based on hierarchical clustering can easily be adapted to different hardware configurations and architectures by changing the size of the clusters. Finally, hierarchical clustering leads to a modular system composed from easy-to-design and hence efficient building blocks.
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