Work

Breadth-first Cycle Collection Reference Counting: Theory and a Rust Smart Pointer Implementation

Year: 2025

Type: conference-paper

Abstract: We present a new garbage collection reference counting algorithm capable of collecting reference cycles—overcoming a known limitation of traditional reference counting. The algorithm's key features include resilience to errors during tracing, support for object finalisation, no need for supplementary heap memory during collection, and a fast breadth-first tracing approach that avoids stack overflows. We implement the algorithm as a Rust library that is idiomatic and highly compatible with the Rust ecosystem and that leverages Rust's type system and borrow checker to minimise unsafe code and prevent undefined behaviour. We report benchmarks that show that our proposal performs comparably to popular Rust alternatives and outperforms them when dealing with garbage cycles.

Source: ACM/SIGAPP Symposium on Applied Computing (SAC)

DOI: 10.1145/3672608.3707785

Authors: Saverio Giallorenzo, Francesco Goretti

Institutions: Institut national de recherche en sciences et technologies du numérique, Centre Inria d'Université Côte d'Azur, University of Bologna

Language: English

Topic: Logic, programming, and type systems

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: hybrid

Funders: Ministero dell'Università e della Ricerca, NextGenerationEU

Award: G5871482690