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> Unreal Engine API Reference > Runtime > Core > GenericPlatform > FGenericPlatformMemory

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FGenericPlatformMemory

Generic implementation for most platforms, these tend to be unused and unimplemented.

Windows

MacOS

Linux

Inheritance Hierarchy

FGenericPlatformMemory

	FHoloLensPlatformMemory
	FUnixPlatformMemory

References

Module	Core
Header	/Engine/Source/Runtime/Core/Public/GenericPlatform/GenericPlatformMemory.h
Include	#include "GenericPlatform/GenericPlatformMemory.h"

Syntax

struct FGenericPlatformMemory

Remarks

Generic implementation for most platforms, these tend to be unused and unimplemented.

Functions

	Name	Description
struct	attribute ( (packed) )	Assume it is either clang or something that supports the clang attributes
FMalloc *...	BaseAllocator()
void *	BigBlockMemcpy ( void* Dest, const void* Src, SIZE_T Count )	Memcpy optimized for big blocks.
void *	BinnedAllocFromOS ( SIZE_T Size )	Allocates pages from the OS.
void	BinnedFreeToOS ( void* Ptr, SIZE_T Size )	Returns pages allocated by BinnedAllocFromOS to the OS.
bool	BinnedPlatformHasMemoryPoolForThisSize ( SIZE_T Size )	Some platforms may pool allocations of this size to reduce OS calls.
void	DumpPlatformAndAllocatorStats ( FOutputDevice& Ar )	Dumps basic platform memory statistics and allocator specific statistics into the specified output device.
void	DumpStats ( FOutputDevice& Ar )	Dumps basic platform memory statistics into the specified output device.
uint32	GetBackMemoryPoolSize()
const FPlatf...	GetConstants()
uint64	GetExtraDevelopmentMemorySize()	Returns >0 if debug memory has been assigned to the title for general use.
bool	GetLLMAllocFunctions ( void(&)(size_t) OutAlloc..., void*, size_t) Ou..., int32& OutAlignment )	This function sets AllocFunction and FreeFunction and returns true, or just returns false.
EPlatformMem...	GetMemorySizeBucket()	Return which "high level", per platform, memory bucket we are in
uint64	GetMemoryUsedFast()
uint32	GetPhysicalGBRam()
FPlatformMem...	GetStats()
void	GetStatsForMallocProfiler ( FGenericMemoryStats& out_Stats )	Writes all platform specific current memory statistics in the format usable by the malloc profiler.
bool	HasForkPageProtectorEnabled()	Returns true if Protecting the parent processes pages has been enabled Only supported on platforms that support forking
void	Init()	Initializes platform memory specific constants.
void	InternalUpdateStats ( const FPlatformMemoryStats& Memory... )	Updates platform specific stats.
bool	IsExtraDevelopmentMemoryAvailable()	Returns true if debug memory has been assigned to the title for general use.
bool	IsNanoMallocAvailable()	Nano Malloc is Apple's tiny block allocator. Does the Nano malloc zone exist?
FSharedMemor...	MapNamedSharedMemoryRegion ( const FString& Name, bool bCreate, uint32 AccessMode, SIZE_T Size )	Maps a named shared memory region into process address space (creates or opens it)
int32	Memcmp ( const void* Buf1, const void* Buf2, SIZE_T Count )
void *	Memcpy ( void* Dest, const void* Src, SIZE_T Count )
void *	Memmove ( void* Dest, const void* Src, SIZE_T Count )	Copies count bytes of characters from Src to Dest.
void *	Memset ( void* Dest, uint8 Char, SIZE_T Count )
void	Memswap ( void* Ptr1, void* Ptr2, SIZE_T Size )
void *	Memzero ( void* Dest, SIZE_T Count )
void	NanoMallocInit()	Performs initial setup for Nano malloc. This is a noop on non-apple platforms
void	OnLowLevelMemory_Alloc ( void const* Pointer, uint64 Size, uint64 Tag )	Called for all default tracker LLM allocations and frees, when LLM is enabled.
void	OnLowLevelMemory_Free ( void const* Pointer, uint64 Size, uint64 Tag )
void	OnOutOfMemory ( uint64 Size, uint32 Alignment )
bool	PageProtect ( void*const Ptr, const SIZE_T Size, const bool bCanRead, const bool bCanWrite )	Changes the protection on a region of committed pages in the virtual address space.
bool	PtrIsFromNanoMalloc ( void* Ptr )	Was this pointer allocated by in the Nano Malloc Zone? Currently only Apple platforms implement this to detect small block allocations.
bool	PtrIsOSMalloc ( void* Ptr )	Was this pointer allocated by the OS malloc? Currently only Apple platforms implement this to detect small block allocations.
T	ReadUnaligned ( const void* Ptr )	Loads a simple POD type from unaligned memory.
void	RegisterCustomLLMTags()	Called once at LLM initialization time to let the platform add any custom tags
void	SetupMemoryPools()	Initializes the memory pools, should be called by the init function.
void *	StreamingMemcpy ( void* Dest, const void* Src, SIZE_T Count )	On some platforms memcpy optimized for big blocks that avoid L2 cache pollution are available
bool	SupportsFastVRAMMemory()	Gets whether this platform supports Fast VRAM memory Ie, whether TexCreate_FastVRAM flags actually mean something or not
bool	UnmapNamedSharedMemoryRegion ( FSharedMemoryRegion* MemoryReg... )	Unmaps a name shared memory region
void	UpdateCustomLLMTags()	Called once per frame when LLM is collating the data for the current frame.
void	WriteUnaligned ( void* Ptr, const T& InValue )	Stores a simple POD type to unaligned memory.

Classes

	Name	Description
	FBasicVirtualMemoryBlock
	FSharedMemoryRegion	Generic representation of a shared memory region

Enums

	Name	Description
	EMemoryAllocatorToUse	Which allocator is being used
	EMemoryCounterRegion	Various memory regions that can be used with memory stats.
	ESharedMemoryAccess	Flags used for shared memory creation/open

Constants

Name	Description
AllocatorToUse	Current allocator
BackupOOMMemoryPool	Preallocated buffer to delete on out of memory. Used by OOM handling and crash reporting.
BackupOOMMemoryPoolSize	Size of BackupOOMMemoryPool in bytes.
bIsOOM	Set to true if we encounters out of memory.
OOMAllocationAlignment	Set to alignment of allocation that triggered out of memory, zero otherwise.
OOMAllocationSize	Set to size of allocation that triggered out of memory, zero otherwise.

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