Handling multiple reserved region lists for numa off-heap case #22694
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LinHu2016 force-pushed the defrag-offheap3_numa branch from dd8b5ac to 041c220 Compare 
amicic reviewed Oct 1, 2025
| */ | ||
| MM_AllocationContextTarok *commonContext = (MM_AllocationContextTarok *)env->getCommonAllocationContext(); | ||
| if (this != commonContext) { | ||
| MM_AllocationContextTarok *context = this; |
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this could be of type MM_AllocationContextBalanced
then this could cast directly with MM_AllocationContextBalanced:
context = (MM_AllocationContextTarok *)env->getCommonAllocationContext();
and there is no need for a cast at a few other places later
LinHu2016 force-pushed the defrag-offheap3_numa branch 2 times, most recently from 1d3fd91 to 4505844 Compare LinHu2016 force-pushed the defrag-offheap3_numa branch 2 times, most recently from 6ffca10 to f9e5f46 Compare 
In PR eclipse-openj9#22116 and eclipse-openj9#22546, _arrayReservedRegionList and _sharedArrayReservedRegionsBytesUsed has been introduced to share fraction of reserved regions. _arrayReservedRegionList is set in commonAllocationContext(single global list), For numa case, the reserved regions for large array could be allocated from different allocation context(allocation context per numa node and in case there is no free region for the numa note, it could borrow from neighbor numa node). during recycling, there are no extra information indicate which reserved regions are for recycling off-heap array, so potentially it might cause imbalance free memory among numa notes, then affect runtime performance in some cases. Undate to manage reserved region list per allocation context(numa note) to avoid imbalance free memory caused by reserved regions. 1, for reducing complexity, shared fraction reserved regions still be managed in _arrayReservedRegionList of commom context. set _sharedReserved in AllocateDescriptor for shared fraction reserved region allocation. 2, new _allocationContextArray in SparseVirtualMemory(omr PR eclipse-omr/omr#7956) to store/retrieve allocation context for the reserved regions of large array. 3, handle allocation failure during getSparseAddressAndDecommitLeaves(). Signed-off-by: lhu <linhu@ca.ibm.com>
Change-Id: Ia3b016fca0c3b1faad9d75617d7ab208aafadb3b Signed-off-by: lhu <linhu@ca.ibm.com>
This reverts commit dd8cf24. Change-Id: Id3d1c9176a18dc2e0a7ac35573b17510e25b9dea
LinHu2016 force-pushed the defrag-offheap3_numa branch from f9e5f46 to 59e5d91 Compare LinHu2016 force-pushed the defrag-offheap3_numa branch from 59e5d91 to 9fc159c Compare Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
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In PR #22116 and #22546, _arrayReservedRegionList and _sharedArrayReservedRegionsBytesUsed has been introduced to share fraction of reserved regions. _arrayReservedRegionList is set in commonAllocationContext(single global list), For numa case, the reserved regions for large array could be allocated from different allocation context(allocation context per numa node and in case there is no free region for the numa note, it could borrow from neighbor numa node). during recycling, there are no extra information indicate which reserved regions are for recycling off-heap array, so potentially it might cause imbalance free memory among numa notes, then affect runtime performance in some cases.
Undate to manage reserved region list per allocation context(numa note) to avoid imbalance free memory caused by reserved regions.
1, for reducing complexity, shared fraction reserved regions still be managed in _arrayReservedRegionList of commom context. set _sharedReserved in AllocateDescriptor for shared fraction reserved region allocation.
2, new _allocationContextArray in SparseVirtualMemory(omr PR eclipse-omr/omr#7956) to store/retrieve allocation context for the reserved regions of large array.
3, handle allocation failure during getSparseAddressAndDecommitLeaves().
#depend: eclipse-omr/omr#7956