Parallel_reader::Ctx Class Reference

Parallel reader execution context. More...

#include <row0pread.h>

Public Member Functions
	Ctx (size_t id, Scan_ctx *scan_ctx, const Scan_ctx::Range &range)
	Constructor. More...
	~Ctx ()=default
	Destructor. More...
size_t	id () const
size_t	scan_id () const
	The scan ID of the scan context this belongs to. More...
const trx_t *	trx () const
const dict_index_t *	index () const
size_t	thread_id () const
Thread_ctx *	thread_ctx () const
size_t	partition_id () const
bool	is_rec_visible (const rec_t *&rec, ulint *&offsets, mem_heap_t *&heap, mtr_t *mtr)
	Build an old version of the row if required. More...

Public Attributes
Thread_ctx *	m_thread_ctx {}
	Context information related to executing thread ID. More...
const buf_block_t *	m_block {}
	Current block. More...
const rec_t *	m_rec {}
	Current row. More...
size_t	m_n_pages {}
	Number of pages traversed by the context. More...
bool	m_first_rec {true}
	True if m_rec is the first record in the page. More...
ulint *	m_offsets {}
bool	m_start {}
	Start of a new range to scan. More...

Private Member Functions
dberr_t	traverse ()
	Traverse the pages by key order. More...
dberr_t	traverse_recs (PCursor *pcursor, mtr_t *mtr)
	Traverse the records in a node. More...
bool	move_to_next_node (PCursor *pcursor)
	Move to the next node in the specified level. More...
dberr_t	split ()
	Split the context into sub-ranges and add them to the execution queue. More...
bool	is_error_set () const

Private Attributes
size_t	m_id {std::numeric_limits<size_t>::max()}
	Context ID. More...
bool	m_split {}
	If true then split the context at the block level. More...
Scan_ctx::Range	m_range {}
	Range to read in this context. More...
Scan_ctx *	m_scan_ctx {}
	Scanner context. More...

Friends
class	Parallel_reader

Detailed Description

Parallel reader execution context.

Constructor & Destructor Documentation

Ctx()

Parallel_reader::Ctx::Ctx ( size_t  id, Scan_ctx *  scan_ctx, const Scan_ctx::Range &  range  )

inline

Constructor.

Parameters

[in]	id	Thread ID.
[in]	scan_ctx	Scan context.
[in]	range	Range that the thread has to read.

~Ctx()

Parallel_reader::Ctx::~Ctx ( )

default

Destructor.

Member Function Documentation

id()

size_t Parallel_reader::Ctx::id ( ) const

inline

Returns

the context ID.

index()

const dict_index_t * Parallel_reader::Ctx::index ( ) const

inline

Returns

the index being scanned.

is_error_set()

bool Parallel_reader::Ctx::is_error_set ( ) const

inlineprivate

Returns

true if in error state.

is_rec_visible()

bool Parallel_reader::Ctx::is_rec_visible ( const rec_t *&  rec, ulint *&  offsets, mem_heap_t *&  heap, mtr_t *  mtr  )

inline

Build an old version of the row if required.

Parameters

[in,out]	rec	Current row read from the index. This can be modified by this method if an older version needs to be built.
[in,out]	offsets	Same as above but pertains to the rec offsets
[in,out]	heap	Heap to use if a previous version needs to be built from the undo log.
[in,out]	mtr	Mini-transaction covering the read.

Returns

true if row is visible to the transaction.

move_to_next_node()

bool Parallel_reader::Ctx::move_to_next_node ( PCursor *  pcursor )

private

Move to the next node in the specified level.

Parameters

[in]

pcursor

persistent b-tree cursor

Returns

success

partition_id()

size_t Parallel_reader::Ctx::partition_id ( ) const

inline

Returns

the partition id of the index.

Note

this is std::numeric_limits<size_t>::max() if the index does not belong to a partition.

scan_id()

size_t Parallel_reader::Ctx::scan_id ( ) const

inline

The scan ID of the scan context this belongs to.

split()

dberr_t Parallel_reader::Ctx::split ( )

private

Split the context into sub-ranges and add them to the execution queue.

Returns

DB_SUCCESS or error code.

thread_ctx()

Thread_ctx * Parallel_reader::Ctx::thread_ctx ( ) const

inline

Returns

the thread context of the reader thread.

thread_id()

size_t Parallel_reader::Ctx::thread_id ( ) const

inline

Returns

ID of the thread processing this context

traverse()

dberr_t Parallel_reader::Ctx::traverse ( )

private

Traverse the pages by key order.

Returns

DB_SUCCESS or error code.

traverse_recs()

dberr_t Parallel_reader::Ctx::traverse_recs ( PCursor *  pcursor, mtr_t *  mtr  )

private

Traverse the records in a node.

Parameters

[in]	pcursor	persistent b-tree cursor
[in]	mtr	mtr

Returns

error

trx()

const trx_t * Parallel_reader::Ctx::trx ( ) const

inline

Returns

the covering transaction.

Friends And Related Function Documentation

Parallel_reader

friend class Parallel_reader

friend

Member Data Documentation

m_block

const buf_block_t* Parallel_reader::Ctx::m_block {}

Current block.

m_first_rec

bool Parallel_reader::Ctx::m_first_rec {true}

True if m_rec is the first record in the page.

m_id

size_t Parallel_reader::Ctx::m_id {std::numeric_limits<size_t>::max()}

private

Context ID.

m_n_pages

size_t Parallel_reader::Ctx::m_n_pages {}

Number of pages traversed by the context.

m_offsets

ulint* Parallel_reader::Ctx::m_offsets {}

m_range

Scan_ctx::Range Parallel_reader::Ctx::m_range {}

private

Range to read in this context.

m_rec

const rec_t* Parallel_reader::Ctx::m_rec {}

Current row.

m_scan_ctx

Scan_ctx* Parallel_reader::Ctx::m_scan_ctx {}

private

Scanner context.

m_split

bool Parallel_reader::Ctx::m_split {}

private

If true then split the context at the block level.

m_start

bool Parallel_reader::Ctx::m_start {}

Start of a new range to scan.

m_thread_ctx

Thread_ctx* Parallel_reader::Ctx::m_thread_ctx {}

Context information related to executing thread ID.

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

• storage/innobase/include/row0pread.h
• storage/innobase/row/row0pread.cc