UE::IoStore::IIasCache Class Reference

#include <IasCache.h>

Inheritance diagram for UE::IoStore::IIasCache:

Public Member Functions
virtual	~IIasCache ()=default
virtual void	Abandon ()=0
virtual void	Drop ()=0
virtual bool	ContainsChunk (const FIoHash &Key) const =0
virtual EIoErrorCode	Get (const FIoHash &Key, FIoBuffer &OutData)=0
virtual void	Materialize (const FIoHash &Key, FIoBuffer &Dest, EIoErrorCode &Status, UE::Tasks::FTaskEvent DoneEvent)=0
virtual void	Cancel (FIoBuffer &GivenDest)=0
virtual FIoStatus	Put (const FIoHash &Key, FIoBuffer &Data)=0
virtual FIoStatus	Evict (const FIoHash &Key)=0

Detailed Description

Cache for binary blobs with a 20 byte cache key.

Constructor & Destructor Documentation

~IIasCache()

virtual UE::IoStore::IIasCache::~IIasCache ( )

virtualdefault

Member Function Documentation

Abandon()

virtual void UE::IoStore::IIasCache::Abandon ( )

pure virtual

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.

Implemented in UE::IoStore::FJournaledCache.

Cancel()

virtual void UE::IoStore::IIasCache::Cancel ( FIoBuffer &  GivenDest )

pure virtual

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.

Implemented in UE::IoStore::FJournaledCache.

ContainsChunk()

virtual bool UE::IoStore::IIasCache::ContainsChunk ( const FIoHash &  Key ) const

pure virtual

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

Implemented in UE::IoStore::FJournaledCache.

Drop()

virtual void UE::IoStore::IIasCache::Drop ( )

pure virtual

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

Implemented in UE::IoStore::FJournaledCache.

Evict()

virtual FIoStatus UE::IoStore::IIasCache::Evict ( const FIoHash &  Key )

pure virtual

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

Implemented in UE::IoStore::FJournaledCache.

Get()

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

pure virtual

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

Implemented in UE::IoStore::FJournaledCache.

Materialize()

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

pure virtual

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.

Implemented in UE::IoStore::FJournaledCache.

Put()

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

pure virtual

Insert a new chunk into the cache.

Implemented in UE::IoStore::FJournaledCache.

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

• Engine/Source/Runtime/Experimental/IoStore/OnDemand/Private/IasCache.h