Innodb_trx_scan_state Class Reference

State of a given scan. More...

Public Member Functions
	Innodb_trx_scan_state ()
	~Innodb_trx_scan_state ()=default
scan_pass	get_pass ()
void	prepare_next_scan ()
	Prepare the next scan. More...
bool	trx_id_in_range (trx_id_t trx_id)
	Check if a transaction belongs to the current range. More...

Public Attributes
const trx_id_t	SCAN_RANGE = 256

Private Attributes
scan_pass	m_scan_pass
	Current scan pass. More...
trx_id_t	m_start_trx_id_range
	Start of the current range. More...
trx_id_t	m_end_trx_id_range
	End of the current range. More...
trx_id_t	m_next_trx_id_range
	Next range. More...

Detailed Description

State of a given scan.

Scans are restartable, and done in multiple calls. Overall, the code scans separately:

• the RW trx list
• the MySQL trx list For each list, the scan is done by ranges of trx_id values. Saving the current scan state allows to resume where the previous scan ended.

Constructor & Destructor Documentation

Innodb_trx_scan_state()

Innodb_trx_scan_state::Innodb_trx_scan_state ( )

inline

~Innodb_trx_scan_state()

Innodb_trx_scan_state::~Innodb_trx_scan_state ( )

default

Member Function Documentation

get_pass()

scan_pass Innodb_trx_scan_state::get_pass ( )

inline

prepare_next_scan()

void Innodb_trx_scan_state::prepare_next_scan ( )

inline

Prepare the next scan.

When there are TRX after the current range, compute the next range. When there are no more TRX for this pass, advance to the next pass.

trx_id_in_range()

bool Innodb_trx_scan_state::trx_id_in_range ( trx_id_t  trx_id )

inline

Check if a transaction belongs to the current range.

As a side effect, compute the next range.

Parameters

[in]

trx_id

Transaction id to evaluate

Returns

True if transaction is within range.

Member Data Documentation

m_end_trx_id_range

trx_id_t Innodb_trx_scan_state::m_end_trx_id_range

private

End of the current range.

m_next_trx_id_range

trx_id_t Innodb_trx_scan_state::m_next_trx_id_range

private

Next range.

m_scan_pass

scan_pass Innodb_trx_scan_state::m_scan_pass

private

Current scan pass.

m_start_trx_id_range

trx_id_t Innodb_trx_scan_state::m_start_trx_id_range

private

Start of the current range.

SCAN_RANGE

const trx_id_t Innodb_trx_scan_state::SCAN_RANGE = 256

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

• storage/innobase/handler/p_s.cc