Yan Huang - CSCI5330 Database Implementation – Parallel Database
Factors Limiting Speedup and Scaleup
Speedup and scaleup are often sublinear due to:
Startup costs: Cost of starting up multiple processes may dominate computation time, if the degree of parallelism is high.
Interference: Processes accessing shared resources (e.g.,system bus, disks, or locks) compete with each other
Skew: Overall execution time determined by slowest of parallely executing tasks.