X. Zhang, Y. Yan, and R. Castaneda, 
``Comparative performance evaluation of hot 
spot contention between MIN-based and ring-based shared-memory architectures", 

IEEE Transactions on Parallel and Distributed Systems, Vol. 6, No. 8, 1995. 

Abstract 
-------- 

Hot spot contention on a network-based shared-memory architecture
occurs when a large number of
processors try to access a globally shared variable across the network.
While Multistage Interconnection Network (MIN) and Hierarchical Ring (HR)
structures are two important bases on which to build large scale shared-memory
multiprocessors, the different interconnection networks and cache/memory
systems of the two architectures respond very differently to
network bottleneck situations.
In this paper, we present a comparative
performance evaluation of hot spot effects on the MIN-based and
HR-based shared-memory architectures.
Both non-blocking
MIN-based and HR-based architectures are classified, and analytical
models are described for understanding network differences
and for evaluating hot spot performance on both architectures.
The analytical comparisons indicate that HR-based architectures
have the potential to handle
various contentions caused by hot spots
more efficiently than MIN-based architectures.
Intensive performance measurements on hot spots have been conducted on the BBN
TC2000 (MIN-based) and the KSR1 (HR-based) machines. Performance
experiments were also conducted on the practical experience of
hot spots with respect to synchronization lock algorithms.
The experimental
results support the analytical models, and present practical
observations and an evaluation of hot spots on the two types of architectures.