An Empirical Study of Selective Optimization

This paper describes an empirical study of the SPECjvm98 benchmarks, using the Jalape~ no virtual machine. The study employs two compilers, a nonoptimizing compiler that is initially used to compile all application methods, and an optimizing compiler that is selectively used to recompile a parameterized set of hot methods based on past prooling. We view this study as a step in examining the feasibility of adaptive optimization in this environment. The results show promise for adaptive optimization. In particular, they show that the combined time (execution and compilation) of selective opt-compilation can be less than the execution time of no opt-compilation and the combined time of full opt-compilation. The results also show that the combined time of selective opt-compilation can be competitive with static compilation (full opt-compilation not counting compilation time) for the SPECjvm98 benchmarks with input size 100.