We call a garbage collector conservative if it has only partial information about the location of pointers and is thus forced to treat arbitrary bit patterns as though they might be pointers in at least some cases We show that some very inexpensive but previously unused tech niques can have dramatic impact on the e ectiveness of conservative garbage collectors in reclaiming mem ory Our most sig...

This paper presents an algorithm for distributed garbage collection and outlines its implementation within the Network Objects system The algorithm is based on a reference listing scheme which is augmented by partial tracing in order to collect distributed garbage cy cles Processes may be dynamically organised into groups according to appropriate heuristics to reclaim distributed garbage cycles...

Our research is concerned with compiler-independent, eecient and convenient garbage collection for C++. Most collectors proposed for C++ have either been implemented in a library or in a compiler. As an intermediate step between those two, this paper proposes using precompilation techniques to augment a C++ source program with code to allow mostly type-accurate garbage collection. There are two...

Current garbage collectors leave much heap-allocated data uncollected because they preserve data reachable from a root set. However, only live data—a subset of reachable data—need be preserved. Using a first-order functional language we formulate a context-sensitive liveness analysis for structured data and prove it correct. We then use a 0-CFA-like conservative approximation to annotate each a...

The possible applications of Java range from small applets to large, data-intensive scientiic applications allocating memory in the multi-gigabyte range. As a consequence copying garbage collectors can not fullll the requirements, as large objects can not be copied eeciently. We analyze the allocation patterns and object lifespans for diierent Java applications and present garbage collection te...

Parameterization of garbage collectors can help improving the overall run time of programs, but finding the best parameter combination is a tedious task. We used a simple brute-force optimization algorithm for the Java Parallel GC to study the behavior of benchmarks with thousands of configurations. As a result of this study, we propose a practically usable strategy for finding a “good” paramet...

Dan Grossman recently wrote a thought-provoking paper entitled “The Transactional Memory / Garbage Collection Analogy” [5], which argues that transactional memory (TM) [11, 8, 20] will bring benefits to the lives of shared-memory parallel programmers that are broadly similar to the benefits commonly attributed to garbage collectors (GCs). This paper examines the TM/GC analogy in detail, paralle...

We argue that garbage collection should be more closely tied to object demographics. We show that this behaviour is sufficiently distinctive to make exploitation feasible and describe a novel GC framework that exploits object lifetime analysis yet tolerates imprecision. We argue for future collectors based on combinations of approximate analyses and dynamic sampling.

Full precision in garbage collection implies retaining only those heap allocated objects that will actually be used in the future. Since full precision is not computable in general, garbage collectors use safe (i.e., conservative) approximations such as reachability from a set of root references. Ambiguous roots collectors (commonly called “conservative”) can be overly conservative because they...

There are many algorithms for concurrent garbage collection, but they are complex to describe, verify, and implement. This has resulted in a poor understanding of the relationships between the algorithms, and has precluded systematic study and comparative evaluation. We present a single high-level, abstract concurrent garbage collection algorithm, and show how existing snapshot and incremental ...