APAR status
Closed as program error.
Error description
Error Message: none . Stack Trace: j9vmem_decommit_memory() MM_VirtualMemory::decommitMemory() MM_MemoryManager::decommitMemory() MM_ConcurrentCardTable::heapRemoveRange() MM_ConcurrentGC::heapRemoveRange() MM_HeapVirtualMemory::heapRemoveRange() MM_MemorySpace::heapRemoveRange() MM_MemorySubSpace::heapRemoveRange() MM_MemorySubSpace::heapRemoveRange() MM_PhysicalSubArenaVirtualMemoryFlat::contract() MM_MemorySubSpace::contract() MM_MemorySubSpaceUniSpace::performResize() MM_ParallelGlobalGC::masterThreadGarbageCollect() MM_ConcurrentGC::internalGarbageCollect() MM_Collector::garbageCollect() MM_MemorySubSpace::systemGarbageCollect() MM_MemorySubSpace::systemGarbageCollect() MM_MemorySpace::systemGarbageCollect() MM_Heap::systemGarbageCollect() j9gc_modron_global_collect_with_() .
Local fix
Couple of workarounds are applicable: 1) Specify -Xms value equal to -Xmx. This would prevent JVM from decommitting any java heap memory. This workaround is applicable to all platforms. 2) On Linux and z/OS, JVM tries to decommit java heap memory only if -Xsoftmx option is specified on the command line. Therefore, removing the -Xsoftmx option to disable decommitting can be used as a workaround on Linux and z/OS only.
Problem summary
The crash happens when GC tries to decommit java heap memory and the memory block to be decommitted is less than the page size used to allocate the java heap.
Problem conclusion
This defect will be fixed in: 7.0.0 SR5 6.0.1 SR6 . JVM has been updated to correctly handle the situations where size of memory block to be decommitted is less than page size.
Temporary fix
Comments
APAR Information
APAR number
IV43553
Reported component name
J9 COMMON CODE
Reported component ID
620700127
Reported release
260
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2013-06-03
Closed date
2013-06-03
Last modified date
2013-06-25
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
J9 COMMON CODE
Fixed component ID
620700127
Applicable component levels
R260 PSY
UP
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Document Information
Modified date:
21 February 2022