Storage provider that reads ntuple pages from a file.

Definition at line 119 of file RPageStorageFile.hxx.

Public Member Functions
	RPageSourceFile (const RPageSourceFile &)=delete

	RPageSourceFile (RPageSourceFile &&)=default

	RPageSourceFile (std::string_view ntupleName, std::string_view path, const RNTupleReadOptions &options)

virtual	~RPageSourceFile ()

std::unique_ptr< RPageSource >	Clone () const final
	The cloned page source creates a new raw file and reader and opens its own file descriptor to the data.

std::vector< std::unique_ptr< RCluster > >	LoadClusters (std::span< RCluster::RKey > clusterKeys) final
	Populates all the pages of the given cluster ids and columns; it is possible that some columns do not contain any pages.

void	LoadSealedPage (DescriptorId_t columnId, const RClusterIndex &clusterIndex, RSealedPage &sealedPage) final
	Read the packed and compressed bytes of a page into the memory buffer provided by selaedPage.

RPageSourceFile &	operator= (const RPageSourceFile &)=delete

RPageSourceFile &	operator= (RPageSourceFile &&)=default

RPage	PopulatePage (ColumnHandle_t columnHandle, const RClusterIndex &clusterIndex) final
	Another version of PopulatePage that allows to specify cluster-relative indexes.

RPage	PopulatePage (ColumnHandle_t columnHandle, NTupleSize_t globalIndex) final
	Allocates and fills a page that contains the index-th element.

void	ReleasePage (RPage &page) final
	Every page store needs to be able to free pages it handed out.

Public Member Functions inherited from ROOT::Experimental::Detail::RPageSource
	RPageSource (const RPageSource &)=delete

	RPageSource (RPageSource &&)=default

	RPageSource (std::string_view ntupleName, const RNTupleReadOptions &fOptions)

virtual	~RPageSource ()

ColumnHandle_t	AddColumn (DescriptorId_t fieldId, const RColumn &column) override
	Register a new column.

void	Attach ()
	Open the physical storage container for the tree.

void	DropColumn (ColumnHandle_t columnHandle) override
	Unregisters a column.

ColumnId_t	GetColumnId (ColumnHandle_t columnHandle)

const RNTupleDescriptor &	GetDescriptor () const

virtual RNTupleMetrics &	GetMetrics () override
	Returns the default metrics object. Subclasses might alternatively override the method and provide their own metrics object.

NTupleSize_t	GetNElements (ColumnHandle_t columnHandle)

NTupleSize_t	GetNEntries ()

const RNTupleReadOptions &	GetReadOptions () const

EPageStorageType	GetType () final
	Whether the concrete implementation is a sink or a source.

RPageSource &	operator= (const RPageSource &)=delete

RPageSource &	operator= (RPageSource &&)=default

void	UnzipCluster (RCluster *cluster)
	Parallel decompression and unpacking of the pages in the given cluster.

Public Member Functions inherited from ROOT::Experimental::Detail::RPageStorage
	RPageStorage (const RPageStorage &other)=delete

	RPageStorage (RPageStorage &&other)=default

	RPageStorage (std::string_view name)

virtual	~RPageStorage ()

const std::string &	GetNTupleName () const
	Returns the NTuple name.

RPageStorage &	operator= (const RPageStorage &other)=delete

RPageStorage &	operator= (RPageStorage &&other)=default

void	SetTaskScheduler (RTaskScheduler *taskScheduler)

Static Public Attributes
static constexpr std::size_t	kMaxPageSize = 1024 * 1024
	Cannot process pages larger than 1MB.

Protected Member Functions
RNTupleDescriptor	AttachImpl () final

void	UnzipClusterImpl (RCluster *cluster) final

Protected Member Functions inherited from ROOT::Experimental::Detail::RPageSource
void	EnableDefaultMetrics (const std::string &prefix)
	Enables the default set of metrics provided by RPageSource.

std::unique_ptr< unsigned char[]>	UnsealPage (const RSealedPage &sealedPage, const RColumnElementBase &element)
	Helper for unstreaming a page.

Private Member Functions
	RPageSourceFile (std::string_view ntupleName, const RNTupleReadOptions &options)

RPage	PopulatePageFromCluster (ColumnHandle_t columnHandle, const RClusterDescriptor &clusterDescriptor, ClusterSize_t::ValueType idxInCluster)

std::unique_ptr< RCluster >	PrepareSingleCluster (const RCluster::RKey &clusterKey, std::vector< ROOT::Internal::RRawFile::RIOVec > &readRequests)
	Helper function for LoadClusters: it prepares the memory buffer (page map) and the read requests for a given cluster and columns.

Private Attributes
std::unique_ptr< RClusterPool >	fClusterPool
	The cluster pool asynchronously preloads the next few clusters.

RCluster *	fCurrentCluster = nullptr
	The last cluster from which a page got populated. Points into fClusterPool->fPool.

std::unique_ptr< ROOT::Internal::RRawFile >	fFile
	An RRawFile is used to request the necessary byte ranges from a local or a remote file.

std::unique_ptr< RPageAllocatorFile >	fPageAllocator
	Populated pages might be shared; there memory buffer is managed by the RPageAllocatorFile.

std::shared_ptr< RPagePool >	fPagePool
	The page pool might, at some point, be used by multiple page sources.

Internal::RMiniFileReader	fReader
	Takes the fFile to read ntuple blobs from it.

Additional Inherited Members
Public Types inherited from ROOT::Experimental::Detail::RPageStorage
using	ColumnHandle_t = RColumnHandle
	The column handle identifies a column with the current open page storage.

Static Public Member Functions inherited from ROOT::Experimental::Detail::RPageSource
static std::unique_ptr< RPageSource >	Create (std::string_view ntupleName, std::string_view location, const RNTupleReadOptions &options=RNTupleReadOptions())
	Guess the concrete derived page source from the file name (location)

Protected Attributes inherited from ROOT::Experimental::Detail::RPageSource
RCluster::ColumnSet_t	fActiveColumns
	The active columns are implicitly defined by the model fields or views.

std::unique_ptr< RCounters >	fCounters

std::unique_ptr< RNTupleDecompressor >	fDecompressor
	Helper to unzip pages and header/footer; comprises a 16MB (kMAXZIPBUF) unzip buffer.

RNTupleDescriptor	fDescriptor

RNTupleMetrics	fMetrics
	Wraps the I/O counters and is observed by the RNTupleReader metrics.

RNTupleReadOptions	fOptions

Protected Attributes inherited from ROOT::Experimental::Detail::RPageStorage
std::string	fNTupleName

RTaskScheduler *	fTaskScheduler = nullptr

#include <ROOT/RPageStorageFile.hxx>

Inheritance diagram for ROOT::Experimental::Detail::RPageSourceFile:

[legend]

Constructor & Destructor Documentation

◆ RPageSourceFile() [1/4]

ROOT::Experimental::Detail::RPageSourceFile::RPageSourceFile	(	std::string_view	ntupleName,
		const RNTupleReadOptions &	options
	)

private

Definition at line 237 of file RPageStorageFile.cxx.

◆ RPageSourceFile() [2/4]

ROOT::Experimental::Detail::RPageSourceFile::RPageSourceFile	(	std::string_view	ntupleName,
		std::string_view	path,
		const RNTupleReadOptions &	options
	)

Definition at line 249 of file RPageStorageFile.cxx.

◆ RPageSourceFile() [3/4]

ROOT::Experimental::Detail::RPageSourceFile::RPageSourceFile ( const RPageSourceFile & )

delete

◆ RPageSourceFile() [4/4]

ROOT::Experimental::Detail::RPageSourceFile::RPageSourceFile ( RPageSourceFile && )

default

◆ ~RPageSourceFile()

ROOT::Experimental::Detail::RPageSourceFile::~RPageSourceFile ( )

virtualdefault

Member Function Documentation

◆ AttachImpl()

ROOT::Experimental::RNTupleDescriptor ROOT::Experimental::Detail::RPageSourceFile::AttachImpl ( )

finalprotectedvirtual

Implements ROOT::Experimental::Detail::RPageSource.

Definition at line 262 of file RPageStorageFile.cxx.

◆ Clone()

std::unique_ptr< ROOT::Experimental::Detail::RPageSource > ROOT::Experimental::Detail::RPageSourceFile::Clone ( ) const

finalvirtual

The cloned page source creates a new raw file and reader and opens its own file descriptor to the data.

The meta-data (header and footer) is reread and parsed by the clone.

Implements ROOT::Experimental::Detail::RPageSource.

Definition at line 411 of file RPageStorageFile.cxx.

◆ LoadClusters()

std::vector< std::unique_ptr< ROOT::Experimental::Detail::RCluster > > ROOT::Experimental::Detail::RPageSourceFile::LoadClusters ( std::span< RCluster::RKey > clusterKeys )

finalvirtual

Populates all the pages of the given cluster ids and columns; it is possible that some columns do not contain any pages.

The page source may load more columns than the minimal necessary set from columns. To indicate which columns have been loaded, LoadClusters() must mark them with SetColumnAvailable(). That includes the ones from the columns that don't have pages; otherwise subsequent requests for the cluster would assume an incomplete cluster and trigger loading again. LoadClusters() is typically called from the I/O thread of a cluster pool, i.e. the method runs concurrently to other methods of the page source.

Implements ROOT::Experimental::Detail::RPageSource.

Definition at line 535 of file RPageStorageFile.cxx.

◆ LoadSealedPage()

void ROOT::Experimental::Detail::RPageSourceFile::LoadSealedPage	(	DescriptorId_t	columnId,
		const RClusterIndex &	clusterIndex,
		RSealedPage &	sealedPage
	)

finalvirtual

Read the packed and compressed bytes of a page into the memory buffer provided by selaedPage.

The sealed page can be used subsequently in a call to RPageSink::CommitSealedPage. The fSize and fNElements member of the sealedPage parameters are always set. If sealedPage.fBuffer is nullptr, no data will be copied but the returned size information can be used by the caller to allocate a large enough buffer and call LoadSealedPage again.

Implements ROOT::Experimental::Detail::RPageSource.

Definition at line 302 of file RPageStorageFile.cxx.

◆ operator=() [1/2]

RPageSourceFile & ROOT::Experimental::Detail::RPageSourceFile::operator= ( const RPageSourceFile & )

delete

◆ operator=() [2/2]

RPageSourceFile & ROOT::Experimental::Detail::RPageSourceFile::operator= ( RPageSourceFile && )

default

◆ PopulatePage() [1/2]

ROOT::Experimental::Detail::RPage ROOT::Experimental::Detail::RPageSourceFile::PopulatePage	(	ColumnHandle_t	columnHandle,
		const RClusterIndex &	clusterIndex
	)

finalvirtual

Another version of PopulatePage that allows to specify cluster-relative indexes.

Implements ROOT::Experimental::Detail::RPageSource.

Definition at line 391 of file RPageStorageFile.cxx.

◆ PopulatePage() [2/2]

ROOT::Experimental::Detail::RPage ROOT::Experimental::Detail::RPageSourceFile::PopulatePage	(	ColumnHandle_t	columnHandle,
		NTupleSize_t	globalIndex
	)

finalvirtual

Allocates and fills a page that contains the index-th element.

Implements ROOT::Experimental::Detail::RPageSource.

Definition at line 374 of file RPageStorageFile.cxx.

◆ PopulatePageFromCluster()

ROOT::Experimental::Detail::RPage ROOT::Experimental::Detail::RPageSourceFile::PopulatePageFromCluster	(	ColumnHandle_t	columnHandle,
		const RClusterDescriptor &	clusterDescriptor,
		ClusterSize_t::ValueType	idxInCluster
	)

private

Definition at line 317 of file RPageStorageFile.cxx.

◆ PrepareSingleCluster()

std::unique_ptr< ROOT::Experimental::Detail::RCluster > ROOT::Experimental::Detail::RPageSourceFile::PrepareSingleCluster	(	const RCluster::RKey &	clusterKey,
		std::vector< ROOT::Internal::RRawFile::RIOVec > &	readRequests
	)

private

Helper function for LoadClusters: it prepares the memory buffer (page map) and the read requests for a given cluster and columns.

The reead requests are appended to the provided vector. This way, requests can be collected for multiple clusters before sending them to RRawFile::ReadV().

Definition at line 420 of file RPageStorageFile.cxx.

◆ ReleasePage()

void ROOT::Experimental::Detail::RPageSourceFile::ReleasePage ( RPage & page )

finalvirtual

Every page store needs to be able to free pages it handed out.

But Sinks and sources have different means of allocating pages.

Implements ROOT::Experimental::Detail::RPageStorage.

Definition at line 406 of file RPageStorageFile.cxx.

◆ UnzipClusterImpl()

void ROOT::Experimental::Detail::RPageSourceFile::UnzipClusterImpl ( RCluster * cluster )

finalprotectedvirtual

Reimplemented from ROOT::Experimental::Detail::RPageSource.

Definition at line 558 of file RPageStorageFile.cxx.

Member Data Documentation

◆ fClusterPool

std::unique_ptr<RClusterPool> ROOT::Experimental::Detail::RPageSourceFile::fClusterPool

private

The cluster pool asynchronously preloads the next few clusters.

Definition at line 136 of file RPageStorageFile.hxx.

◆ fCurrentCluster

RCluster* ROOT::Experimental::Detail::RPageSourceFile::fCurrentCluster = nullptr

private

The last cluster from which a page got populated. Points into fClusterPool->fPool.

Definition at line 130 of file RPageStorageFile.hxx.

◆ fFile

std::unique_ptr<ROOT::Internal::RRawFile> ROOT::Experimental::Detail::RPageSourceFile::fFile

private

An RRawFile is used to request the necessary byte ranges from a local or a remote file.

Definition at line 132 of file RPageStorageFile.hxx.

◆ fPageAllocator

std::unique_ptr<RPageAllocatorFile> ROOT::Experimental::Detail::RPageSourceFile::fPageAllocator

private

Populated pages might be shared; there memory buffer is managed by the RPageAllocatorFile.

Definition at line 126 of file RPageStorageFile.hxx.

◆ fPagePool

std::shared_ptr<RPagePool> ROOT::Experimental::Detail::RPageSourceFile::fPagePool

private

The page pool might, at some point, be used by multiple page sources.

Definition at line 128 of file RPageStorageFile.hxx.

◆ fReader

Internal::RMiniFileReader ROOT::Experimental::Detail::RPageSourceFile::fReader

private

Takes the fFile to read ntuple blobs from it.

Definition at line 134 of file RPageStorageFile.hxx.

◆ kMaxPageSize

constexpr std::size_t ROOT::Experimental::Detail::RPageSourceFile::kMaxPageSize = 1024 * 1024

staticconstexpr

Cannot process pages larger than 1MB.

Definition at line 122 of file RPageStorageFile.hxx.

Libraries for ROOT::Experimental::Detail::RPageSourceFile:

[legend]

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

tree/ntuple/v7/inc/ROOT/RPageStorageFile.hxx
tree/ntuple/v7/src/RPageStorageFile.cxx

Public Member Functions

Static Public Attributes

Protected Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ RPageSourceFile() [1/4]

◆ RPageSourceFile() [2/4]

◆ RPageSourceFile() [3/4]

◆ RPageSourceFile() [4/4]

◆ ~RPageSourceFile()

Member Function Documentation

◆ AttachImpl()

◆ Clone()

◆ LoadClusters()

◆ LoadSealedPage()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ PopulatePage() [1/2]

◆ PopulatePage() [2/2]

◆ PopulatePageFromCluster()

◆ PrepareSingleCluster()

◆ ReleasePage()

◆ UnzipClusterImpl()

Member Data Documentation

◆ fClusterPool

◆ fCurrentCluster

◆ fFile

◆ fPageAllocator

◆ fPagePool

◆ fReader

◆ kMaxPageSize