Remove Double Mapping - #23495
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@amicic @dmitripivkine the changes is ready for review, Thanks |
Balanced GC’s new off-heap feature (enabled by default) now covers all double-mapping use cases with better performance. Since the off-heap feature has proven stable, there is no longer a need to maintain double-mapping as a fallback mechanism. This change removes all double-mapping code to simplify the implementation. - remove the code under preprocessor symbol "J9VM_GC_ENABLE_DOUBLE_MAP" - except gc_glue_java isDoubleMappingEnabled(), which has dependance on omr OMR_GC_DOUBLE_MAP_ARRAYLETS. Signed-off-by: lhu <linhu@ca.ibm.com>
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jenkins test sanity amac jdk21 |
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jenkins compile win jdk8 |
| #endif /* defined(J9VM_GC_ENABLE_DOUBLE_MAP) */ | ||
| continue; | ||
| } | ||
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I think we should not remove these options and keep them around for command line compatibility. Make them do nothing I guess.
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since the testing has passed, I'll let this be handled in a followup PR (when we eventually remove isDoubleMappingEnabled())
amicic
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Mar 12, 2026
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Balanced GC’s new off-heap feature (enabled by default) now covers all double-mapping use cases with better performance. Since the off-heap feature has proven stable, there is no longer a need to maintain double-mapping as a fallback mechanism. This change removes all double-mapping code to simplify the implementation.