RTL_HEAP_PARAMETERS - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers
#ifndef _NTRTL_H

typedef struct _RTL_HEAP_PARAMETERS
{
    ULONG Length;
    SIZE_T SegmentReserve;
    SIZE_T SegmentCommit;
    SIZE_T DeCommitFreeBlockThreshold;
    SIZE_T DeCommitTotalFreeThreshold;
    SIZE_T MaximumAllocationSize;
    SIZE_T VirtualMemoryThreshold;
    SIZE_T InitialCommit;
    SIZE_T InitialReserve;
    PRTL_HEAP_COMMIT_ROUTINE CommitRoutine;
    SIZE_T Reserved[2];
} RTL_HEAP_PARAMETERS, *PRTL_HEAP_PARAMETERS;

#endif

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This structure is documented in Windows Driver Kit.