A column is a storage-backed array of a simple, fixed-size type, from which pages can be mapped into memory.

Definition at line 42 of file RColumn.hxx.

Public Member Functions
	RColumn (const RColumn &)=delete

	~RColumn ()

void	Append (const void *from)

void	AppendV (const void *from, std::size_t count)

void	CommitSuppressed ()

void	ConnectPageSink (DescriptorId_t fieldId, RPageSink &pageSink, NTupleSize_t firstElementIndex=0U)
	Connect the column to a page sink.

void	ConnectPageSource (DescriptorId_t fieldId, RPageSource &pageSource)
	Connect the column to a page source.

void	Flush ()

std::uint16_t	GetBitsOnStorage () const

RClusterIndex	GetClusterIndex (NTupleSize_t globalIndex)

void	GetCollectionInfo (const NTupleSize_t globalIndex, RClusterIndex collectionStart, ClusterSize_t collectionSize)
	For offset columns only, look at the two adjacent values that define a collection's coordinates.

void	GetCollectionInfo (RClusterIndex clusterIndex, RClusterIndex collectionStart, ClusterSize_t collectionSize)

ColumnId_t	GetColumnIdSource () const

RColumnElementBase *	GetElement () const

NTupleSize_t	GetFirstElementIndex () const

NTupleSize_t	GetGlobalIndex (RClusterIndex clusterIndex)

RPageStorage::ColumnHandle_t	GetHandleSink () const

RPageStorage::ColumnHandle_t	GetHandleSource () const

std::uint32_t	GetIndex () const

NTupleSize_t	GetNElements () const

RPageSink *	GetPageSink () const

RPageSource *	GetPageSource () const

std::uint16_t	GetRepresentationIndex () const

void	GetSwitchInfo (NTupleSize_t globalIndex, RClusterIndex varIndex, std::uint32_t tag)
	Get the currently active cluster id.

EColumnType	GetType () const

template<typename CppT >
CppT *	Map (const NTupleSize_t globalIndex)

template<typename CppT >
CppT *	Map (RClusterIndex clusterIndex)

void	MapPage (NTupleSize_t globalIndex)

void	MapPage (RClusterIndex clusterIndex)

template<typename CppT >
CppT *	MapV (const NTupleSize_t globalIndex, NTupleSize_t &nItems)

template<typename CppT >
CppT *	MapV (RClusterIndex clusterIndex, NTupleSize_t &nItems)

void	MergeTeams (RColumn &other)

RColumn &	operator= (const RColumn &)=delete

void	Read (const NTupleSize_t globalIndex, void *to)

void	Read (RClusterIndex clusterIndex, void *to)

bool	ReadPageContains (NTupleSize_t globalIndex) const

bool	ReadPageContains (RClusterIndex clusterIndex) const

void	ReadV (const NTupleSize_t globalIndex, const ClusterSize_t::ValueType count, void *to)

void	ReadV (RClusterIndex clusterIndex, const ClusterSize_t::ValueType count, void *to)

bool	TryMapPage (NTupleSize_t globalIndex)

bool	TryMapPage (RClusterIndex clusterIndex)

Static Public Member Functions
template<typename CppT >
static std::unique_ptr< RColumn >	Create (EColumnType type, std::uint32_t columnIdx, std::uint16_t representationIdx)

Private Member Functions
	RColumn (EColumnType type, std::uint32_t columnIndex, std::uint16_t representationIndex)

void	FlushShadowWritePage ()
	When the main write page surpasses the 50% fill level, the (full) shadow write page gets flushed.

void	HandleWritePageIfFull ()
	Used in Append() and AppendV() to handle the case when the main page reached the target size.

Private Attributes
std::uint32_t	fApproxNElementsPerPage = 0
	For writing, the targeted number of elements, given by `fApproxNElementsPerPage` (in the write options) and the element size.

std::uint16_t	fBitsOnStorage = 0

ColumnId_t	fColumnIdSource = kInvalidColumnId
	The column id is used to find matching pages with content when reading.

std::unique_ptr< RColumnElementBase >	fElement
	Used to pack and unpack pages on writing/reading.

NTupleSize_t	fFirstElementIndex = 0
	Global index of the first element in this column; usually == 0, unless it is a deferred column.

RPageStorage::ColumnHandle_t	fHandleSink

RPageStorage::ColumnHandle_t	fHandleSource

std::uint32_t	fIndex
	Columns belonging to the same field are distinguished by their order.

std::size_t	fLastGoodTeamIdx = 0
	Points into fTeam to the column that successfully returned the last page.

NTupleSize_t	fNElements = 0
	The number of elements written resp. available in the column.

RPageSink *	fPageSink = nullptr

RPageSource *	fPageSource = nullptr

RPageRef	fReadPageRef
	The currently mapped page for reading.

std::uint16_t	fRepresentationIndex
	Fields can have multiple column representations, distinguished by representation index.

std::vector< RColumn * >	fTeam
	The column team is a set of columns that serve the same column index for different representation IDs.

EColumnType	fType

RPage	fWritePage [2]
	A set of open pages into which new elements are being written.

int	fWritePageIdx = 0
	Index of the current write page.

#include <ROOT/RColumn.hxx>

Constructor & Destructor Documentation

◆ RColumn() [1/2]

ROOT::Experimental::Internal::RColumn::RColumn	(	EColumnType	type,
		std::uint32_t	columnIndex,
		std::uint16_t	representationIndex
	)

private

Definition at line 26 of file RColumn.cxx.

◆ RColumn() [2/2]

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

delete

◆ ~RColumn()

ROOT::Experimental::Internal::RColumn::~RColumn ( )

Definition at line 36 of file RColumn.cxx.

Member Function Documentation

◆ Append()

void ROOT::Experimental::Internal::RColumn::Append ( const void * from )

inline

Definition at line 141 of file RColumn.hxx.

◆ AppendV()

void ROOT::Experimental::Internal::RColumn::AppendV	(	const void *	from,
		std::size_t	count
	)

inline

Definition at line 155 of file RColumn.hxx.

◆ CommitSuppressed()

void ROOT::Experimental::Internal::RColumn::CommitSuppressed ( )

Definition at line 98 of file RColumn.cxx.

◆ ConnectPageSink()

void ROOT::Experimental::Internal::RColumn::ConnectPageSink	(	DescriptorId_t	fieldId,
		RPageSink &	pageSink,
		NTupleSize_t	firstElementIndex = `0U`
	)

Connect the column to a page sink.

firstElementIndex can be used to specify the first column element index with backing storage for this column. On read back, elements before firstElementIndex will cause the zero page to be mapped.

Definition at line 44 of file RColumn.cxx.

◆ ConnectPageSource()

void ROOT::Experimental::Internal::RColumn::ConnectPageSource	(	DescriptorId_t	fieldId,
		RPageSource &	pageSource
	)

Connect the column to a page source.

Definition at line 65 of file RColumn.cxx.

◆ Create()

template<typename CppT >

static std::unique_ptr< RColumn > ROOT::Experimental::Internal::RColumn::Create	(	EColumnType	type,
		std::uint32_t	columnIdx,
		std::uint16_t	representationIdx
	)

inlinestatic

Definition at line 123 of file RColumn.hxx.

◆ Flush()

void ROOT::Experimental::Internal::RColumn::Flush ( )

Definition at line 77 of file RColumn.cxx.

◆ FlushShadowWritePage()

void ROOT::Experimental::Internal::RColumn::FlushShadowWritePage ( )

inlineprivate

When the main write page surpasses the 50% fill level, the (full) shadow write page gets flushed.

Definition at line 110 of file RColumn.hxx.

◆ GetBitsOnStorage()

std::uint16_t ROOT::Experimental::Internal::RColumn::GetBitsOnStorage ( ) const

inline

Definition at line 359 of file RColumn.hxx.

◆ GetClusterIndex()

RClusterIndex ROOT::Experimental::Internal::RColumn::GetClusterIndex ( NTupleSize_t globalIndex )

inline

Definition at line 293 of file RColumn.hxx.

◆ GetCollectionInfo() [1/2]

void ROOT::Experimental::Internal::RColumn::GetCollectionInfo	(	const NTupleSize_t	globalIndex,
		RClusterIndex *	collectionStart,
		ClusterSize_t *	collectionSize
	)

inline

For offset columns only, look at the two adjacent values that define a collection's coordinates.

Definition at line 303 of file RColumn.hxx.

◆ GetCollectionInfo() [2/2]

void ROOT::Experimental::Internal::RColumn::GetCollectionInfo	(	RClusterIndex	clusterIndex,
		RClusterIndex *	collectionStart,
		ClusterSize_t *	collectionSize
	)

inline

Definition at line 326 of file RColumn.hxx.

◆ GetColumnIdSource()

ColumnId_t ROOT::Experimental::Internal::RColumn::GetColumnIdSource ( ) const

inline

Definition at line 362 of file RColumn.hxx.

◆ GetElement()

RColumnElementBase * ROOT::Experimental::Internal::RColumn::GetElement ( ) const

inline

Definition at line 357 of file RColumn.hxx.

◆ GetFirstElementIndex()

NTupleSize_t ROOT::Experimental::Internal::RColumn::GetFirstElementIndex ( ) const

inline

Definition at line 363 of file RColumn.hxx.

◆ GetGlobalIndex()

NTupleSize_t ROOT::Experimental::Internal::RColumn::GetGlobalIndex ( RClusterIndex clusterIndex )

inline

Definition at line 285 of file RColumn.hxx.

◆ GetHandleSink()

RPageStorage::ColumnHandle_t ROOT::Experimental::Internal::RColumn::GetHandleSink ( ) const

inline

Definition at line 367 of file RColumn.hxx.

◆ GetHandleSource()

RPageStorage::ColumnHandle_t ROOT::Experimental::Internal::RColumn::GetHandleSource ( ) const

inline

Definition at line 366 of file RColumn.hxx.

◆ GetIndex()

std::uint32_t ROOT::Experimental::Internal::RColumn::GetIndex ( ) const

inline

Definition at line 360 of file RColumn.hxx.

◆ GetNElements()

NTupleSize_t ROOT::Experimental::Internal::RColumn::GetNElements ( ) const

inline

Definition at line 356 of file RColumn.hxx.

◆ GetPageSink()

RPageSink * ROOT::Experimental::Internal::RColumn::GetPageSink ( ) const

inline

Definition at line 365 of file RColumn.hxx.

◆ GetPageSource()

RPageSource * ROOT::Experimental::Internal::RColumn::GetPageSource ( ) const

inline

Definition at line 364 of file RColumn.hxx.

◆ GetRepresentationIndex()

std::uint16_t ROOT::Experimental::Internal::RColumn::GetRepresentationIndex ( ) const

inline

Definition at line 361 of file RColumn.hxx.

◆ GetSwitchInfo()

void ROOT::Experimental::Internal::RColumn::GetSwitchInfo	(	NTupleSize_t	globalIndex,
		RClusterIndex *	varIndex,
		std::uint32_t *	tag
	)

inline

Get the currently active cluster id.

Definition at line 336 of file RColumn.hxx.

◆ GetType()

EColumnType ROOT::Experimental::Internal::RColumn::GetType ( ) const

inline

Definition at line 358 of file RColumn.hxx.

◆ HandleWritePageIfFull()

void ROOT::Experimental::Internal::RColumn::HandleWritePageIfFull ( )

inlineprivate

Used in Append() and AppendV() to handle the case when the main page reached the target size.

If tail page optimization is enabled, switch the pages; the other page has been flushed when the main page reached 50%. Without tail page optimization, flush the current page to make room for future writes.

Definition at line 92 of file RColumn.hxx.

◆ Map() [1/2]

template<typename CppT >

CppT * ROOT::Experimental::Internal::RColumn::Map ( const NTupleSize_t globalIndex )

inline

Definition at line 246 of file RColumn.hxx.

◆ Map() [2/2]

template<typename CppT >

CppT * ROOT::Experimental::Internal::RColumn::Map ( RClusterIndex clusterIndex )

inline

Definition at line 253 of file RColumn.hxx.

◆ MapPage() [1/2]

void ROOT::Experimental::Internal::RColumn::MapPage ( NTupleSize_t globalIndex )

inline

Definition at line 346 of file RColumn.hxx.

◆ MapPage() [2/2]

void ROOT::Experimental::Internal::RColumn::MapPage ( RClusterIndex clusterIndex )

inline

Definition at line 347 of file RColumn.hxx.

◆ MapV() [1/2]

template<typename CppT >

CppT * ROOT::Experimental::Internal::RColumn::MapV	(	const NTupleSize_t	globalIndex,
		NTupleSize_t &	nItems
	)

inline

Definition at line 260 of file RColumn.hxx.

◆ MapV() [2/2]

template<typename CppT >

CppT * ROOT::Experimental::Internal::RColumn::MapV	(	RClusterIndex	clusterIndex,
		NTupleSize_t &	nItems
	)

inline

Definition at line 273 of file RColumn.hxx.

◆ MergeTeams()

void ROOT::Experimental::Internal::RColumn::MergeTeams ( RColumn & other )

Definition at line 133 of file RColumn.cxx.

◆ operator=()

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

delete

◆ Read() [1/2]

void ROOT::Experimental::Internal::RColumn::Read	(	const NTupleSize_t	globalIndex,
		void *	to
	)

inline

Definition at line 185 of file RColumn.hxx.

◆ Read() [2/2]

void ROOT::Experimental::Internal::RColumn::Read	(	RClusterIndex	clusterIndex,
		void *	to
	)

inline

Definition at line 196 of file RColumn.hxx.

◆ ReadPageContains() [1/2]

bool ROOT::Experimental::Internal::RColumn::ReadPageContains ( NTupleSize_t globalIndex ) const

inline

Definition at line 351 of file RColumn.hxx.

◆ ReadPageContains() [2/2]

bool ROOT::Experimental::Internal::RColumn::ReadPageContains ( RClusterIndex clusterIndex ) const

inline

Definition at line 352 of file RColumn.hxx.

◆ ReadV() [1/2]

void ROOT::Experimental::Internal::RColumn::ReadV	(	const NTupleSize_t	globalIndex,
		const ClusterSize_t::ValueType	count,
		void *	to
	)

inline

Definition at line 207 of file RColumn.hxx.

◆ ReadV() [2/2]

void ROOT::Experimental::Internal::RColumn::ReadV	(	RClusterIndex	clusterIndex,
		const ClusterSize_t::ValueType	count,
		void *	to
	)

inline

Definition at line 226 of file RColumn.hxx.

◆ TryMapPage() [1/2]

bool ROOT::Experimental::Internal::RColumn::TryMapPage ( NTupleSize_t globalIndex )

Definition at line 103 of file RColumn.cxx.

◆ TryMapPage() [2/2]

bool ROOT::Experimental::Internal::RColumn::TryMapPage ( RClusterIndex clusterIndex )

Definition at line 118 of file RColumn.cxx.

Member Data Documentation

◆ fApproxNElementsPerPage

std::uint32_t ROOT::Experimental::Internal::RColumn::fApproxNElementsPerPage = 0

private

For writing, the targeted number of elements, given by fApproxNElementsPerPage (in the write options) and the element size.

We ensure this value to be >= 2 in Connect() so that we have meaningful "page full" and "page half full" events when writing the page.

Definition at line 67 of file RColumn.hxx.

◆ fBitsOnStorage

std::uint16_t ROOT::Experimental::Internal::RColumn::fBitsOnStorage = 0

private

Definition at line 45 of file RColumn.hxx.

◆ fColumnIdSource

ColumnId_t ROOT::Experimental::Internal::RColumn::fColumnIdSource = kInvalidColumnId

private

The column id is used to find matching pages with content when reading.

Definition at line 73 of file RColumn.hxx.

◆ fElement

std::unique_ptr<RColumnElementBase> ROOT::Experimental::Internal::RColumn::fElement

private

Used to pack and unpack pages on writing/reading.

Definition at line 77 of file RColumn.hxx.

◆ fFirstElementIndex

NTupleSize_t ROOT::Experimental::Internal::RColumn::fFirstElementIndex = 0

private

Global index of the first element in this column; usually == 0, unless it is a deferred column.

Definition at line 75 of file RColumn.hxx.

◆ fHandleSink

RPageStorage::ColumnHandle_t ROOT::Experimental::Internal::RColumn::fHandleSink

private

Definition at line 53 of file RColumn.hxx.

◆ fHandleSource

RPageStorage::ColumnHandle_t ROOT::Experimental::Internal::RColumn::fHandleSource

private

Definition at line 54 of file RColumn.hxx.

◆ fIndex

std::uint32_t ROOT::Experimental::Internal::RColumn::fIndex

private

Columns belonging to the same field are distinguished by their order.

E.g. for an std::string field, there is the offset column with index 0 and the character value column with index 1.

Definition at line 48 of file RColumn.hxx.

◆ fLastGoodTeamIdx

std::size_t ROOT::Experimental::Internal::RColumn::fLastGoodTeamIdx = 0

private

Points into fTeam to the column that successfully returned the last page.

Definition at line 84 of file RColumn.hxx.

◆ fNElements

NTupleSize_t ROOT::Experimental::Internal::RColumn::fNElements = 0

private

The number of elements written resp. available in the column.

Definition at line 69 of file RColumn.hxx.

◆ fPageSink

RPageSink* ROOT::Experimental::Internal::RColumn::fPageSink = nullptr

private

Definition at line 51 of file RColumn.hxx.

◆ fPageSource

RPageSource* ROOT::Experimental::Internal::RColumn::fPageSource = nullptr

private

Definition at line 52 of file RColumn.hxx.

◆ fReadPageRef

RPageRef ROOT::Experimental::Internal::RColumn::fReadPageRef

private

The currently mapped page for reading.

Definition at line 71 of file RColumn.hxx.

◆ fRepresentationIndex

std::uint16_t ROOT::Experimental::Internal::RColumn::fRepresentationIndex

private

Fields can have multiple column representations, distinguished by representation index.

Definition at line 50 of file RColumn.hxx.

◆ fTeam

std::vector<RColumn *> ROOT::Experimental::Internal::RColumn::fTeam

private

The column team is a set of columns that serve the same column index for different representation IDs.

Initially, the team has only one member, the very column it belongs to. Through MergeTeams(), two columns can join forces. The team is used to react on suppressed columns: if the current team member has a suppressed column for a MapPage() call, it get the page from the active column in the corresponding cluster.

Definition at line 82 of file RColumn.hxx.

◆ fType

EColumnType ROOT::Experimental::Internal::RColumn::fType

private

Definition at line 44 of file RColumn.hxx.

◆ fWritePage

RPage ROOT::Experimental::Internal::RColumn::fWritePage[2]

private

A set of open pages into which new elements are being written.

The pages are used in rotation. If tail page optimization is enabled, they are 50% bigger than the target size given by the write options. The current page is filled until the target size, but it is only committed once the other write page is filled at least 50%. If a flush occurs earlier, a slightly oversized, single page will be committed. Without tail page optimization, only one page is allocated equal to the target size.

Definition at line 61 of file RColumn.hxx.

◆ fWritePageIdx

int ROOT::Experimental::Internal::RColumn::fWritePageIdx = 0

private

Index of the current write page.

Definition at line 63 of file RColumn.hxx.

Libraries for ROOT::Experimental::Internal::RColumn:

[legend]

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

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

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Constructor & Destructor Documentation

◆ RColumn() [1/2]

◆ RColumn() [2/2]

◆ ~RColumn()

Member Function Documentation

◆ Append()

◆ AppendV()

◆ CommitSuppressed()

◆ ConnectPageSink()

◆ ConnectPageSource()

◆ Create()

◆ Flush()

◆ FlushShadowWritePage()

◆ GetBitsOnStorage()

◆ GetClusterIndex()

◆ GetCollectionInfo() [1/2]

◆ GetCollectionInfo() [2/2]

◆ GetColumnIdSource()

◆ GetElement()

◆ GetFirstElementIndex()

◆ GetGlobalIndex()

◆ GetHandleSink()

◆ GetHandleSource()

◆ GetIndex()

◆ GetNElements()

◆ GetPageSink()

◆ GetPageSource()

◆ GetRepresentationIndex()

◆ GetSwitchInfo()

◆ GetType()

◆ HandleWritePageIfFull()

◆ Map() [1/2]

◆ Map() [2/2]

◆ MapPage() [1/2]

◆ MapPage() [2/2]

◆ MapV() [1/2]

◆ MapV() [2/2]

◆ MergeTeams()

◆ operator=()

◆ Read() [1/2]

◆ Read() [2/2]

◆ ReadPageContains() [1/2]

◆ ReadPageContains() [2/2]

◆ ReadV() [1/2]

◆ ReadV() [2/2]

◆ TryMapPage() [1/2]

◆ TryMapPage() [2/2]

Member Data Documentation

◆ fApproxNElementsPerPage

◆ fBitsOnStorage

◆ fColumnIdSource

◆ fElement

◆ fFirstElementIndex

◆ fHandleSink

◆ fHandleSource

◆ fIndex

◆ fLastGoodTeamIdx

◆ fNElements

◆ fPageSink

◆ fPageSource

◆ fReadPageRef

◆ fRepresentationIndex

◆ fTeam

◆ fType

◆ fWritePage

◆ fWritePageIdx