UE::IoStore::FJournaledCache Class Reference

Inheritance diagram for UE::IoStore::FJournaledCache:

Public Member Functions
	FJournaledCache (FDiskCacheGovernor &DiskCacheGovernor)
	~FJournaledCache ()
bool	Initialize (const TCHAR *RootDir, const FIasCacheConfig &Config)
virtual void	Abandon () override
virtual void	Drop () override
virtual bool	ContainsChunk (const FIoHash &Key) const override
virtual EIoErrorCode	Get (const FIoHash &Key, FIoBuffer &OutData) override
virtual void	Materialize (const FIoHash &Key, FIoBuffer &Dest, EIoErrorCode &Status, UE::Tasks::FTaskEvent DoneEvent) override
virtual void	Cancel (FIoBuffer &GivenDest) override
virtual FIoStatus	Put (const FIoHash &Key, FIoBuffer &Data) override
virtual FIoStatus	Evict (const FIoHash &Key) override
Public Member Functions inherited from UE::IoStore::IIasCache
virtual	~IIasCache ()=default

Constructor & Destructor Documentation

FJournaledCache()

UE::IoStore::FJournaledCache::FJournaledCache

(

FDiskCacheGovernor &

DiskCacheGovernor

)

~FJournaledCache()

UE::IoStore::FJournaledCache::~FJournaledCache

(

)

Member Function Documentation

Abandon()

void UE::IoStore::FJournaledCache::Abandon ( )

overridevirtual

Deletes the IAS object, dropping all data persisted to disk and releasing OS resources. As this also deletes the object thus any unique pointers should be released prior to abandonment; TUniquePtr->Release()->Abandon(). Be sure to cancel and collect any Get() tasks beforehand.

Implements UE::IoStore::IIasCache.

Cancel()

void UE::IoStore::FJournaledCache::Cancel ( FIoBuffer &  GivenDest )

overridevirtual

Cancels a previously request to Materialize(). Note that the materialize already can still complete as the read operation may already be in flight. If the cancel succeeds, the materialize's DoneEvent is not triggered.

Implements UE::IoStore::IIasCache.

ContainsChunk()

bool UE::IoStore::FJournaledCache::ContainsChunk ( const FIoHash &  Key ) const

overridevirtual

Returns whether the specified cache key is present in the cache.

Implements UE::IoStore::IIasCache.

Drop()

void UE::IoStore::FJournaledCache::Drop ( )

overridevirtual

Clears out the cache and resets it back to the default state.

Implements UE::IoStore::IIasCache.

Evict()

FIoStatus UE::IoStore::FJournaledCache::Evict ( const FIoHash &  Key )

overridevirtual

Evict an item from the cache. For example it might be corrupt

Implements UE::IoStore::IIasCache.

Get()

EIoErrorCode UE::IoStore::FJournaledCache::Get ( const FIoHash &  Key, FIoBuffer &  OutData  )

overridevirtual

Get the chunk associated with the specified cache key. If the data is already in memory it is return in OutData. Otherwise the returned status indicates if the key can be materialized or if it does not exist

Implements UE::IoStore::IIasCache.

Initialize()

bool UE::IoStore::FJournaledCache::Initialize	(	const TCHAR *	RootDir,
		const FIasCacheConfig &	Config
	)

Materialize()

void UE::IoStore::FJournaledCache::Materialize ( const FIoHash &  Key, FIoBuffer &  Dest, EIoErrorCode &  Status, UE::Tasks::FTaskEvent  DoneEvent  )

overridevirtual

Materializes a cached items data from disk. The data is read into Dest so Dest must remain valid throughout. The result of the disk read is returned in Status (same lifetime needs as Dest). DoneEvent is triggered when the read succeeds, is not found, or if an IO error occurred.

Implements UE::IoStore::IIasCache.

Put()

FIoStatus UE::IoStore::FJournaledCache::Put ( const FIoHash &  Key, FIoBuffer &  Data  )

overridevirtual

Insert a new chunk into the cache.

Implements UE::IoStore::IIasCache.

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The documentation for this class was generated from the following file:

• Engine/Source/Runtime/Experimental/IoStore/OnDemand/Private/JournaledCache.cpp