Decreasing Memory Overhead in Hard Real-Time Garbage Collection

  • Tobias Ritzau
  • Peter Fritzson
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2491)


Automatic memory management techniques eliminate many programming errors that are both hard to find and to correct. However, these techniques are not yet used in embedded systems with hard realtime applications. The reason is that current methods for automatic memory management have a number of drawbacks. The two major ones are: (1) not being able to always guarantee short real-time deadlines and (2) using large amounts of extra memory. Memory is usually a scarce resource in embedded applications.

In this paper we present a new technique, Real-Time Reference Counting (RTRC) that overcomes the current problems and makes automatic memory management attractive also for hard real-time applications. The main contribution of RTRC is that often all memory can be used to store live objects. This should be compared to a memory overhead of about 500% for garbage collectors based on copying techniques and about 50% for garbage collectors based on mark-and-sweep techniques.


Execution Time Garbage Collection Garbage Collector Memory Overhead Free List 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Tobias Ritzau
    • 1
  • Peter Fritzson
    • 1
  1. 1.Department of Computer and Information ScienceLinköping UniversityLinköpingSweden

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