Distributed Garbage Collection for Mobile Actor Systems: The Pseudo Root Approach

  • Wei-Jen Wang
  • Carlos A. Varela
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3947)


Automatic distributed garbage collection (GC) gives abstraction to grid application development, promoting code quality and improving resource management. Unreachability of active objects or actors from the root set is not a sufficient condition to collect actor garbage, making passive object GC algorithms unsafe when directly used on actor systems. In practical actor languages, all actors have references to the root set since they can interact with users, e.g., through standard input or output streams. Based on this observation, we introduce pseudo roots: a dynamic set of actors that can be viewed as the root set. Pseudo roots use protected (undeletable) references to ensure that no actors are erroneously collected even with messages in transit. Following this idea, we introduce a new direction of actor GC, and demonstrate it by developing a distributed GC framework. The framework can thus be used for automatic life time management of mobile reactive processes with unordered asynchronous communication.


Computing Node Root Actor Garbage Collection Garbage Collector Passive Object 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Wei-Jen Wang
    • 1
  • Carlos A. Varela
    • 1
  1. 1.Department of Computer ScienceRensselaer Polytechnic InstituteTroyUSA

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