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CHAPTER
7 Scalable Multiprocessors
64 KB. Thus, on a machine with 256-KB caches, the miss rate drops from 5% to 1%
as the configuration scales from four to sixteen or more processors. Indeed, the sum
of the computational time over all the processors drops as the configuration scales,
so perfect speedup is obtained even though the time spent communicating increases.
This effect is less pronounced on the SP-2 because the basic node is optimized for
operation on data that does not fit in the cache.
7.9 SYNCHRONIZATION
Scalability is a primary concern in the combination of software and hardware that
implements synchronization operations in