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  1. JDK
  2. JDK-6765745

par compact - allow young gen spaces to be split

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Details

    • Enhancement
    • Resolution: Fixed
    • P3
    • hs14
    • 5.0u6
    • hotspot
    • None
    • gc
    • b02
    • b09
    • generic
    • generic

    Backports

      Description

        During a full gc, all live objects in the young gen are copied to the old gen as long as there is enough space. When the heap is very full, all the young gen objects may not fit. With par compaction, this often results in a long series of time-consuming full gcs which do not free up space in eden. When par compact is copying from a young gen space (e.g., eden or from) to the old gen, *all* live objects in the space must fit into the old gen; otherwise, none of them will be copied. This is because par compaction operates on fixed-size 'regions' of the heap and copying only part of a space would require extra bookkeeping (or some good luck).

        The extra bookkeeping should be implemented to allow a young gen space to be "split" so that as much as will fit is copied to the old gen and the rest is compacted down within the young gen space itself.

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            backported by

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-2172862 par compact - allow young gen spaces to be split

            • P3 - Major loss of function.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-2172401 par compact - allow young gen spaces to be split

            • P3 - Major loss of function.
            • Closed
            relates to

            Bug - A problem which impairs or prevents the functions of the product. JDK-6330863 vm/gc/InfiniteList.java fails intermittently due to timeout problems

            • P3 - Major loss of function.
            • Closed

            Bug - A problem which impairs or prevents the functions of the product. JDK-6810474 par compact - crash in summary_phase with very full heap

            • P3 - Major loss of function.
            • Closed

            Enhancement - null JDK-6679764 enable parallel compaction by default

            • P3 - Major loss of function.
            • Closed

            Bug - A problem which impairs or prevents the functions of the product. JDK-6784849 par compact - can fail when to_space is non-empty

            • P3 - Major loss of function.
            • Closed

            Enhancement - null JDK-6765954 par compact - stress mode for splitting young gen spaces

            • P3 - Major loss of function.
            • Resolved

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                jcoomes John Coomes (Inactive)
                jcoomes John Coomes (Inactive)
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