Storage provider that reads ntuple pages from a file.

Definition at line 117 of file RPageStorageFile.hxx.

Classes
struct	RStructureBuffer
	Holds the uncompressed header and footer. More...

Public Member Functions
	RPageSourceFile (const RPageSourceFile &)=delete

	RPageSourceFile (RPageSourceFile &&)=delete

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

	RPageSourceFile (std::string_view ntupleName, std::unique_ptr< ROOT::Internal::RRawFile > file, const RNTupleReadOptions &options)

	~RPageSourceFile () override

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 physicalColumnId, RClusterIndex clusterIndex, RSealedPage &sealedPage) final
	Read the packed and compressed bytes of a page into the memory buffer provided by `sealedPage`.

RPageSourceFile &	operator= (const RPageSourceFile &)=delete

RPageSourceFile &	operator= (RPageSourceFile &&)=delete

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

	RPageSource (RPageSource &&)=delete

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

	~RPageSource () override

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

void	Attach ()
	Open the physical storage container and deserialize header and footer.

std::unique_ptr< RPageSource >	Clone () const
	Open the same storage multiple time, e.g.

void	DropColumn (ColumnHandle_t columnHandle) override
	Unregisters a column.

ColumnId_t	GetColumnId (ColumnHandle_t columnHandle)

REntryRange	GetEntryRange () const

NTupleSize_t	GetNElements (ColumnHandle_t columnHandle)

NTupleSize_t	GetNEntries ()

const RNTupleReadOptions &	GetReadOptions () const

const RSharedDescriptorGuard	GetSharedDescriptorGuard () const
	Takes the read lock for the descriptor.

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

virtual RPageRef	LoadPage (ColumnHandle_t columnHandle, NTupleSize_t globalIndex)
	Allocates and fills a page that contains the index-th element.

virtual RPageRef	LoadPage (ColumnHandle_t columnHandle, RClusterIndex clusterIndex)
	Another version of `LoadPage` that allows to specify cluster-relative indexes.

void	LoadStructure ()
	Loads header and footer without decompressing or deserializing them.

RPageSource &	operator= (const RPageSource &)=delete

RPageSource &	operator= (RPageSource &&)=delete

void	SetEntryRange (const REntryRange &range)
	Promise to only read from the given entry range.

RResult< RPage >	UnsealPage (const RSealedPage &sealedPage, const RColumnElementBase &element, DescriptorId_t physicalColumnId)
	Helper for unstreaming a page.

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

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

	RPageStorage (RPageStorage &&other)=default

	RPageStorage (std::string_view name)

virtual	~RPageStorage ()

virtual Detail::RNTupleMetrics &	GetMetrics ()
	Returns the default metrics object.

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 Member Functions
static std::unique_ptr< RPageSourceFile >	CreateFromAnchor (const RNTuple &anchor, const RNTupleReadOptions &options=RNTupleReadOptions())
	Used from the RNTuple class to build a datasource if the anchor is already available.

Static Public Member Functions inherited from ROOT::Experimental::Internal::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 Member Functions
RNTupleDescriptor	AttachImpl () final
	`LoadStructureImpl()` has been called before `AttachImpl()` is called

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

RPageRef	LoadPageImpl (ColumnHandle_t columnHandle, const RClusterInfo &clusterInfo, ClusterSize_t::ValueType idxInCluster) final

void	LoadStructureImpl () final

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

RExclDescriptorGuard	GetExclDescriptorGuard ()
	Note that the underlying lock is not recursive. See `GetSharedDescriptorGuard()` for further information.

void	PrepareLoadCluster (const RCluster::RKey &clusterKey, ROnDiskPageMap &pageZeroMap, std::function< void(DescriptorId_t, NTupleSize_t, const RClusterDescriptor::RPageRange::RPageInfo &)> perPageFunc)
	Prepare a page range read for the column set in `clusterKey`.

virtual void	UnzipClusterImpl (RCluster *cluster)

Protected Member Functions inherited from ROOT::Experimental::Internal::RPageStorage
void	WaitForAllTasks ()

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

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::optional< RNTuple >	fAnchor
	Either provided by CreateFromAnchor, or read from the ROOT file given the ntuple name.

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 loaded. Points into fClusterPool->fPool.

RNTupleDescriptorBuilder	fDescriptorBuilder
	The descriptor is created from the header and footer either in AttachImpl or in CreateFromAnchor.

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

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

RStructureBuffer	fStructureBuffer
	Populated by LoadStructureImpl(), reset at the end of Attach()

Friends
class	ROOT::Experimental::RNTuple

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

using	SealedPageSequence_t = std::deque< RSealedPage >

Static Public Attributes inherited from ROOT::Experimental::Internal::RPageStorage
static constexpr std::size_t	kNBytesPageChecksum = sizeof(std::uint64_t)
	The page checksum is a 64bit xxhash3.

Protected Attributes inherited from ROOT::Experimental::Internal::RPageSource
RActivePhysicalColumns	fActivePhysicalColumns
	The active columns are implicitly defined by the model fields or views.

std::unique_ptr< RCounters >	fCounters

RNTupleReadOptions	fOptions

RPagePool	fPagePool
	Pages that are unzipped with IMT are staged into the page pool.

Protected Attributes inherited from ROOT::Experimental::Internal::RPageStorage
Detail::RNTupleMetrics	fMetrics

std::string	fNTupleName

std::unique_ptr< RPageAllocator >	fPageAllocator
	For the time being, we will use the heap allocator for all sources and sinks. This may change in the future.

RTaskScheduler *	fTaskScheduler = nullptr

#include <ROOT/RPageStorageFile.hxx>

Inheritance diagram for ROOT::Experimental::Internal::RPageSourceFile:

[legend]

Constructor & Destructor Documentation

◆ RPageSourceFile() [1/5]

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

private

Definition at line 257 of file RPageStorageFile.cxx.

◆ RPageSourceFile() [2/5]

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

Definition at line 275 of file RPageStorageFile.cxx.

◆ RPageSourceFile() [3/5]

ROOT::Experimental::Internal::RPageSourceFile::RPageSourceFile	(	std::string_view	ntupleName,
		std::unique_ptr< ROOT::Internal::RRawFile >	file,
		const RNTupleReadOptions &	options
	)

Definition at line 265 of file RPageStorageFile.cxx.

◆ RPageSourceFile() [4/5]

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

delete

◆ RPageSourceFile() [5/5]

ROOT::Experimental::Internal::RPageSourceFile::RPageSourceFile ( RPageSourceFile && )

delete

◆ ~RPageSourceFile()

ROOT::Experimental::Internal::RPageSourceFile::~RPageSourceFile ( )

overridedefault

Member Function Documentation

◆ AttachImpl()

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

finalprotectedvirtual

LoadStructureImpl() has been called before AttachImpl() is called

Implements ROOT::Experimental::Internal::RPageSource.

Definition at line 360 of file RPageStorageFile.cxx.

◆ CloneImpl()

std::unique_ptr< ROOT::Experimental::Internal::RPageSource > ROOT::Experimental::Internal::RPageSourceFile::CloneImpl ( ) const

finalprotectedvirtual

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

Implements ROOT::Experimental::Internal::RPageSource.

Definition at line 484 of file RPageStorageFile.cxx.

◆ CreateFromAnchor()

std::unique_ptr< ROOT::Experimental::Internal::RPageSourceFile > ROOT::Experimental::Internal::RPageSourceFile::CreateFromAnchor	(	const RNTuple &	anchor,
		const RNTupleReadOptions &	options = `RNTupleReadOptions()`
	)

static

Used from the RNTuple class to build a datasource if the anchor is already available.

Requires the RNTuple object to be streamed from a file.

Definition at line 282 of file RPageStorageFile.cxx.

◆ LoadClusters()

std::vector< std::unique_ptr< ROOT::Experimental::Internal::RCluster > > ROOT::Experimental::Internal::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 withSetColumnAvailable(). That includes the ones from thecolumnsthat 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::Internal::RPageSource.

Definition at line 612 of file RPageStorageFile.cxx.

◆ LoadPageImpl()

ROOT::Experimental::Internal::RPageRef ROOT::Experimental::Internal::RPageSourceFile::LoadPageImpl	(	ColumnHandle_t	columnHandle,
		const RClusterInfo &	clusterInfo,
		ClusterSize_t::ValueType	idxInCluster
	)

finalprotectedvirtual

Implements ROOT::Experimental::Internal::RPageSource.

Definition at line 422 of file RPageStorageFile.cxx.

◆ LoadSealedPage()

void ROOT::Experimental::Internal::RPageSourceFile::LoadSealedPage	(	DescriptorId_t	physicalColumnId,
		RClusterIndex	clusterIndex,
		RSealedPage &	sealedPage
	)

finalvirtual

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

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::Internal::RPageSource.

Definition at line 393 of file RPageStorageFile.cxx.

◆ LoadStructureImpl()

void ROOT::Experimental::Internal::RPageSourceFile::LoadStructureImpl ( )

finalprotectedvirtual

Implements ROOT::Experimental::Internal::RPageSource.

Definition at line 311 of file RPageStorageFile.cxx.

◆ operator=() [1/2]

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

delete

◆ operator=() [2/2]

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

delete

◆ PrepareSingleCluster()

std::unique_ptr< ROOT::Experimental::Internal::RCluster > ROOT::Experimental::Internal::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 493 of file RPageStorageFile.cxx.

Friends And Related Symbol Documentation

◆ ROOT::Experimental::RNTuple

friend class ROOT::Experimental::RNTuple

friend

Definition at line 118 of file RPageStorageFile.hxx.

Member Data Documentation

◆ fAnchor

std::optional<RNTuple> ROOT::Experimental::Internal::RPageSourceFile::fAnchor

private

Either provided by CreateFromAnchor, or read from the ROOT file given the ntuple name.

Definition at line 136 of file RPageStorageFile.hxx.

◆ fClusterPool

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

private

The cluster pool asynchronously preloads the next few clusters.

Definition at line 146 of file RPageStorageFile.hxx.

◆ fCurrentCluster

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

private

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

Definition at line 138 of file RPageStorageFile.hxx.

◆ fDescriptorBuilder

RNTupleDescriptorBuilder ROOT::Experimental::Internal::RPageSourceFile::fDescriptorBuilder

private

The descriptor is created from the header and footer either in AttachImpl or in CreateFromAnchor.

Definition at line 144 of file RPageStorageFile.hxx.

◆ fFile

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

private

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

Definition at line 140 of file RPageStorageFile.hxx.

◆ fReader

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

private

Takes the fFile to read ntuple blobs from it.

Definition at line 142 of file RPageStorageFile.hxx.

◆ fStructureBuffer

RStructureBuffer ROOT::Experimental::Internal::RPageSourceFile::fStructureBuffer

private

Populated by LoadStructureImpl(), reset at the end of Attach()

Definition at line 148 of file RPageStorageFile.hxx.

Libraries for ROOT::Experimental::Internal::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

Classes

Public Member Functions

Static Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Friends

Additional Inherited Members

Constructor & Destructor Documentation

◆ RPageSourceFile() [1/5]

◆ RPageSourceFile() [2/5]

◆ RPageSourceFile() [3/5]

◆ RPageSourceFile() [4/5]

◆ RPageSourceFile() [5/5]

◆ ~RPageSourceFile()

Member Function Documentation

◆ AttachImpl()

◆ CloneImpl()

◆ CreateFromAnchor()

◆ LoadClusters()

◆ LoadPageImpl()

◆ LoadSealedPage()

◆ LoadStructureImpl()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ PrepareSingleCluster()

Friends And Related Symbol Documentation

◆ ROOT::Experimental::RNTuple

Member Data Documentation

◆ fAnchor

◆ fClusterPool

◆ fCurrentCluster

◆ fDescriptorBuilder

◆ fFile

◆ fReader

◆ fStructureBuffer