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  1. JDK
  2. JDK-8253779

Amalloc may be wasting space by overaligning

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    Details

    • Type: Enhancement
    • Status: Resolved
    • Priority: P4
    • Resolution: Fixed
    • Affects Version/s: 16
    • Fix Version/s: 18
    • Component/s: hotspot
    • Labels:
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    • Subcomponent:
    • Resolved In Build:
      b06

      Description

      Arena::Amalloc aligns the requested size, so that the the returned pointer is always nicely aligned. The problem is that it aligns to 2*BytesPerWord, which means that on 64bit platforms it is aligning to 16 bytes, which seems wasteful. Do we actually need 16 byte alignment somewhere on 64bit platforms? Or is this 32bit code that didn't get updated for 64bit support. Dredging through old repositories, I think it might be the latter.

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              Assignee:
              coleenp Coleen Phillimore
              Reporter:
              kbarrett Kim Barrett
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                Updated:
                Resolved: