| | |
Summary: Utilizing Field Usage Patterns for Java Heap Space
Optimization
Zhuang Guo Jos´e Nelson Amaral Duane Szafron Yang Wang
Department of Computing Science
University of Alberta, Edmonton, Canada
{zhuang,amaral,duane,yangwang}@cs.ualberta.ca
Abstract
This research studies the characteristics of field
usage patterns in the SpecJVM98 benchmarks. It
finds that multiple object instances of the same
class often exhibit different field-usage patterns.
Motivated by this observation, we designed a heap
compression mechanism that classifies object in-
stances at runtime based on their field-usage pat-
terns and eliminates unused fields to save space.
To achieve the maximum space savings while min-
imizing the space and time overhead, our design
combines three interrelated techniques in a novel
manner: runtime object instance classification, field
virtualization, and bidirectional object layout. An
|
