Inherits AZ::IO::StreamStackEntry.

Classes
struct	ConstructionOptions

struct	FileReadInformation

struct	FileReadStatus

Public Member Functions
	StorageDriveWin (const AZStd::vector< AZStd::string_view > &drivePaths, u32 maxFileHandles, u32 maxMetaDataCacheEntries, size_t physicalSectorSize, size_t logicalSectorSize, u32 ioChannelCount, s32 overCommit, ConstructionOptions options)

void	PrepareRequest (FileRequest *request) override

void	QueueRequest (FileRequest *request) override

bool	ExecuteRequests () override

void	UpdateStatus (Status &status) const override
	Gets a combined status update from all the nodes in the stack.

void	UpdateCompletionEstimates (AZStd::chrono::steady_clock::time_point now, AZStd::vector< FileRequest * > &internalPending, StreamerContext::PreparedQueue::iterator pendingBegin, StreamerContext::PreparedQueue::iterator pendingEnd) override

void	CollectStatistics (AZStd::vector< Statistic > &statistics) const override

Public Member Functions inherited from AZ::IO::StreamStackEntry
	StreamStackEntry (AZStd::string &&name)

virtual const AZStd::string &	GetName () const
	Returns the name that uniquely identifies this entry.

virtual void	SetNext (AZStd::shared_ptr< StreamStackEntry > next)

virtual AZStd::shared_ptr< StreamStackEntry >	GetNext () const

virtual void	SetContext (StreamerContext &context)

virtual void	PrepareRequest (FileRequest *request)

virtual void	QueueRequest (FileRequest *request)

virtual bool	ExecuteRequests ()

virtual void	UpdateStatus (Status &status) const
	Gets a combined status update from all the nodes in the stack.

virtual void	UpdateCompletionEstimates (AZStd::chrono::steady_clock::time_point now, AZStd::vector< FileRequest * > &internalPending, StreamerContext::PreparedQueue::iterator pendingBegin, StreamerContext::PreparedQueue::iterator pendingEnd)

virtual void	CollectStatistics (AZStd::vector< Statistic > &statistics) const

Protected Types
enum class	OpenFileResult { FileOpened , RequestForwarded , CacheFull }

Protected Member Functions
OpenFileResult	OpenFile (HANDLE &fileHandle, size_t &cacheSlot, FileRequest *request, const Requests::ReadData &data)

bool	ReadRequest (FileRequest *request)

bool	ReadRequest (FileRequest *request, size_t readSlot)

bool	CancelRequest (FileRequest *cancelRequest, FileRequestPtr &target)

void	FileExistsRequest (FileRequest *request)

void	FileMetaDataRetrievalRequest (FileRequest *request)

size_t	FindInFileHandleCache (const RequestPath &filePath) const

size_t	FindAvailableFileHandleCacheIndex () const

size_t	FindAvailableReadSlot ()

size_t	FindInMetaDataCache (const RequestPath &filePath) const

size_t	GetNextMetaDataCacheSlot ()

bool	IsServicedByThisDrive (AZ::IO::PathView filePath) const

void	EstimateCompletionTimeForRequest (FileRequest request, AZStd::chrono::steady_clock::time_point &startTime, const RequestPath &activeFile, u64 &activeOffset) const

void	EstimateCompletionTimeForRequestChecked (FileRequest request, AZStd::chrono::steady_clock::time_point startTime, const RequestPath &activeFile, u64 &activeOffset) const

s32	CalculateNumAvailableSlots () const

void	FlushCache (const RequestPath &filePath)

void	FlushEntireCache ()

bool	FinalizeReads ()

void	FinalizeSingleRequest (FileReadStatus &status, size_t readSlot, DWORD numBytesTransferred, bool isCanceled, bool encounteredError)

void	Report (const Requests::ReportData &data) const

Protected Attributes
TimedAverageWindow< s_statisticsWindowSize >	m_fileOpenCloseTimeAverage

TimedAverageWindow< s_statisticsWindowSize >	m_getFileExistsTimeAverage

TimedAverageWindow< s_statisticsWindowSize >	m_getFileMetaDataRetrievalTimeAverage

TimedAverageWindow< s_statisticsWindowSize >	m_readTimeAverage

AverageWindow< u64, float, s_statisticsWindowSize >	m_readSizeAverage

AZStd::chrono::steady_clock::time_point	m_activeReads_startTime

AZStd::deque< FileRequest * >	m_pendingReadRequests

AZStd::deque< FileRequest * >	m_pendingRequests

AZStd::vector< FileReadInformation >	m_readSlots_readInfo

AZStd::vector< FileReadStatus >	m_readSlots_statusInfo

AZStd::vector< bool >	m_readSlots_active

AZStd::vector< AZStd::chrono::steady_clock::time_point >	m_fileCache_lastTimeUsed

AZStd::vector< RequestPath >	m_fileCache_paths

AZStd::vector< HANDLE >	m_fileCache_handles

AZStd::vector< u16 >	m_fileCache_activeReads

AZStd::vector< RequestPath >	m_metaDataCache_paths

AZStd::vector< u64 >	m_metaDataCache_fileSize

AZStd::vector< AZStd::string >	m_drivePaths

size_t	m_activeReads_ByteCount { 0 }

size_t	m_physicalSectorSize { 0 }

size_t	m_logicalSectorSize { 0 }

size_t	m_activeCacheSlot { InvalidFileCacheIndex }

size_t	m_metaDataCache_front { 0 }

u64	m_activeOffset { 0 }

u32	m_maxFileHandles { 1 }

u32	m_ioChannelCount { 1 }

s32	m_overCommit { 0 }

u16	m_activeReads_Count { 0 }

ConstructionOptions	m_constructionOptions

bool	m_cachesInitialized { false }

Protected Attributes inherited from AZ::IO::StreamStackEntry
AZStd::string	m_name
	The name that uniquely identifies this entry.

AZStd::shared_ptr< StreamStackEntry >	m_next
	The next entry in the stack.

StreamerContext *	m_context
	Context information for the entire streaming stack.

Static Protected Attributes
static const AZStd::chrono::microseconds	s_averageSeekTime

static constexpr size_t	InvalidFileCacheIndex = std::numeric_limits<size_t>::max()

static constexpr size_t	InvalidReadSlotIndex = std::numeric_limits<size_t>::max()

static constexpr size_t	InvalidMetaDataCacheIndex = std::numeric_limits<size_t>::max()

Constructor & Destructor Documentation

◆ StorageDriveWin()

AZ::IO::StorageDriveWin::StorageDriveWin	(	const AZStd::vector< AZStd::string_view > &	drivePaths,
		u32	maxFileHandles,
		u32	maxMetaDataCacheEntries,
		size_t	physicalSectorSize,
		size_t	logicalSectorSize,
		u32	ioChannelCount,
		s32	overCommit,
		ConstructionOptions	options
	)

Creates an instance of a storage device that's optimized for use on Windows.

Parameters

drivePaths	The paths to the drives that are supported by this device. A single device can have multiple logical disks.
maxFileHandles	The maximum number of file handles that are cached. Only a small number are needed when running from archives, but it's recommended that a larger number are kept open when reading from loose files.
maxMetaDataCacheEntires	The maximum number of files to keep meta data, such as the file size, to cache. Only a small number are needed when running from archives, but it's recommended that a larger number are kept open when reading from loose files.
physicalSectorSize	The minimal sector size as instructed by the device. When unbuffered reads are used the output buffer needs to be aligned to this value.
logicalSectorSize	The minimal sector size as instructed by the device. When unbuffered reads are used the file size and read offset need to be aligned to this value.
ioChannelCount	The maximum number of requests that the IO controller driving the device supports. This value will be capped by the maximum number of parallel requests that can be issued per thread.
overCommit	The number of additional slots that will be reported as available. This makes sure that there are always a few requests pending to avoid starvation. An over-commit that is too large can negatively impact the scheduler's ability to re-order requests for optimal read order. A negative value will under-commit and will avoid saturating the IO controller which can be needed if the drive is used by other applications.
options	Additional configuration options. See ConstructionOptions for more details.

Member Function Documentation

◆ CollectStatistics()

void AZ::IO::StorageDriveWin::CollectStatistics ( AZStd::vector< Statistic > & statistics ) const

overridevirtual

Collect various statistics on this stack entry. These are for profiling and debugging purposes only.

Reimplemented from AZ::IO::StreamStackEntry.

◆ ExecuteRequests()

bool AZ::IO::StorageDriveWin::ExecuteRequests ( )

overridevirtual

Executes one or more queued requests. This is needed for synchronously executing requests, but asynchronous requests can already be running from the PrepareRequest call in which case this call is ignored.

Returns: True if a request was processed, otherwise false.

Reimplemented from AZ::IO::StreamStackEntry.

◆ PrepareRequest()

void AZ::IO::StorageDriveWin::PrepareRequest ( FileRequest * request )

overridevirtual

Prepare an external request for processing. This can include resolving file paths, create more specific internal requests, etc. The returned will be queued for further processing by QueueRequest and ExecuteRequest.

Reimplemented from AZ::IO::StreamStackEntry.

◆ QueueRequest()

void AZ::IO::StorageDriveWin::QueueRequest ( FileRequest * request )

overridevirtual

Queues a request to be executed at a later point when ExecuteRequests is called. This can include splitting up the request in more fine-grained steps.

Reimplemented from AZ::IO::StreamStackEntry.

◆ UpdateCompletionEstimates()

void AZ::IO::StorageDriveWin::UpdateCompletionEstimates	(	AZStd::chrono::steady_clock::time_point	now,
		AZStd::vector< FileRequest * > &	internalPending,
		StreamerContext::PreparedQueue::iterator	pendingBegin,
		StreamerContext::PreparedQueue::iterator	pendingEnd
	)

overridevirtual

Updates the estimate of the time the requests will complete. This generally works by bubbling up the estimation and each stack entry adding it's additional overhead if any. When chaining this call, first call the next entry in the stack before adding the current entry's estimate.

Parameters

now	The current time. This is captured once to avoid repeatedly querying the system clock.
internalPending	The requests that are pending in the stream stack. These are always estimated as coming after the queued requests. Because this call will go from the top of the stack to the bottom, but estimation is calculated from the bottom to the top, this list should be processed in reverse order.
pendingBegin	Iterator pointing to the start of the requests that are waiting for a processing slot in the stack.
pendingEnd	Iterator pointing to the end of the requests that are waiting for a processing slot in the stack.

Reimplemented from AZ::IO::StreamStackEntry.

◆ UpdateStatus()

void AZ::IO::StorageDriveWin::UpdateStatus ( Status & status ) const

overridevirtual

Gets a combined status update from all the nodes in the stack.

Reimplemented from AZ::IO::StreamStackEntry.

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

Code/Framework/AzCore/Platform/Windows/AzCore/IO/Streamer/StorageDrive_Windows.h

Classes

Public Member Functions

Protected Types

Protected Member Functions

Protected Attributes

Static Protected Attributes

Constructor & Destructor Documentation

◆ StorageDriveWin()

Member Function Documentation

◆ CollectStatistics()

◆ ExecuteRequests()

◆ PrepareRequest()

◆ QueueRequest()

◆ UpdateCompletionEstimates()

◆ UpdateStatus()