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A Study of Java Demographics

Jones, Richard E. and Ryder, Chris (2008) A Study of Java Demographics. In: Blackburn, Steve, ed. ISMM '08 Proceedings of the 7th international symposium on Memory management. ISMM International Symposium on Memory Management . ACM, New York, USA, pp. 121-130. ISBN 978-1-60558-134-7. (doi:10.1145/1375634.1375652) (KAR id:23979)

Language: English
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Researchers have long strived to exploit program behaviour in order to improve garbage collection efficiency. For example, by using a simple heuristic, generational GC manages short-lived objects well, although longer-lived objects will still be promoted to an older generation and may be processed repeatedly thereafter. In this paper, we provide a detailed study of Java object lifetimes which reveals a richer landscape than the generational view offers. Allocation site has been claimed to be a good predictor for object lifetime, but we show that object lifetime can be categorised more precisely than 'short-lived/long-lived/immortal'. We show that (i) sites allocate objects with lifetimes in only a small number of narrow ranges, and (ii) sites cluster strongly with respect to the lifetime distributions of the objects they allocate. Furthermore, (iii) these clusterings are robust against the size of the input given to the program and (iv) are likely to allocate objects that are live only in particular phases of the program's execution. Finally, we show that, in contrast to previous studies, (v) allocation site alone is not always sufficient as a predictor of object lifetime distribution but one further level of stack context suffices.

Item Type: Book section
DOI/Identification number: 10.1145/1375634.1375652
Uncontrolled keywords: Memory management, Garbage collection, Java
Subjects: Q Science > QA Mathematics (inc Computing science) > QA 76 Software, computer programming,
Divisions: Divisions > Division of Computing, Engineering and Mathematical Sciences > School of Computing
Depositing User: Richard Jones
Date Deposited: 29 Mar 2010 12:09 UTC
Last Modified: 16 Nov 2021 10:02 UTC
Resource URI: (The current URI for this page, for reference purposes)
Jones, Richard E.:
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