ORCA is a concurrent and parallel garbage collector for actor programs, which does not require any STW steps, or synchronization mechanisms, and that has been designed to support zero-copy message passing and sharing of mutable data. ORCA is part of a runtime for actor-based languages, which was co-designed with the Pony programming language, and in particular, with its data race free type system. By co-designing an actor language with its runtime, it was possible to exploit certain language properties in order to optimize performance of garbage collection. Namely, ORCA relies on the guarantees of absence of race conditions in order to avoid read/write barriers, and it leverages the actor message passing, for synchronization among actors.
In this paper we briefly describe Pony and its type system. We use pseudo-code in order to introduce how ORCA allocates and deallocates objects, how it shares mutable data without requiring barriers upon data mutation, and how can immutability be used to further optimize garbage collection. Moreover, we discuss the advantages of co-designing an actor language with its runtime, and we demonstrate that ORCA can be implemented in a performant and scalable way through a set of micro-benchmarks, including a comparison with other well-known collectors.
Conference DayThu 26 OctDisplayed time zone: Tijuana, Baja California change
10:30 - 12:00
|Familia: Unifying Interfaces, Type Classes, and Family Polymorphism|
|Static Stages for Heterogeneous Programming|
|Orca: GC and Type System Co-Design for Actor Languages|
Sylvan ClebschImperial College London, Juliana FrancoImperial College London, Sophia Drossopoulou, Albert Mingkun Yang, Tobias WrigstadUppsala University, Jan VitekNortheastern University, USADOI
|Monadic Composition for Deterministic, Parallel Batch Processing|
Ryan ScottIndiana University, Omar Navarro-LeijaUniversity of Pennsylvania, USA, Ryan R. NewtonIndiana University, Joseph DeviettiUniversity of PennsylvaniaDOI