Add groupCount/groupMasks to CACHE_RELATIONSHIP#1720
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dbwiddis merged 1 commit intojava-native-access:masterfrom May 10, 2026
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Add groupCount/groupMasks to CACHE_RELATIONSHIP#1720dbwiddis merged 1 commit intojava-native-access:masterfrom
dbwiddis merged 1 commit intojava-native-access:masterfrom
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Closes java-native-access#1674 The Windows CACHE_RELATIONSHIP struct was updated to use 2 of its reserved bytes for a GroupCount field and replace the single GroupMask with a variable-length GroupMasks array, matching the same change previously made to NUMA_NODE_RELATIONSHIP. Shrink reserved from 20 to 18 bytes, add groupCount (short) and groupMasks array with a read() override to handle both old and new struct layouts.
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Makes sense to me. Thank you.
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Add groupCount/groupMasks to CACHE_RELATIONSHIP
The Windows
CACHE_RELATIONSHIPstruct was updated (Windows Server 2022 / 21H2) to repurpose 2 of its 20 reserved bytes as aGroupCountfield and replace the singleGroupMaskwith a variable-lengthGroupMasksarray. This is the same change documented in #1324 forNUMA_NODE_RELATIONSHIP.Changes
reservedfrom 20 to 18 bytesgroupCount(short) fieldgroupMasks(GROUP_AFFINITY[]) arraygroupMaskas a public compatibility field (populated fromgroupMasks[0])read()to dynamically size the array based ongroupCountgetFieldList()to exclude the compatibilitygroupMaskfield from structure validationSources
GroupCountandGroupMasksfieldsNUMA_NODE_RELATIONSHIPimplementation in this repo (same pattern applied in #1563)Backward compatibility
On older Windows versions where
GroupCountis 0 (the bytes were previously reserved/zeroed), theread()override forces a minimum array size of 1 and copies the value togroupMask, preserving existing behavior.Closes #1674