mysql::csa::Sync_transaction_provider Class Reference

Implementation of 'Transaction_provider' interface. More...

#include <sync_transaction_provider.h>

Inheritance diagram for mysql::csa::Sync_transaction_provider:

Public Member Functions
	Sync_transaction_provider (int instance_id, Relay_log_info *rli, std::size_t max_read_event_bytes, std::size_t max_read_payload_bytes)
void	start () override
	Starts asynchronous thread that decodes jobs from the stream. More...
void	stop () override
	Stops provider and wakes blocked reader calls. More...
void	finish () override
	Completes provider shutdown from the owner thread (transaction receiver). More...
Job_ptr	next () override
	Consumes the next Job, blocks until fetched. More...
bool	is_stopped () const override
	Checks if stop has been requested. More...
bool	is_error () const override
	Check if provider has an error. More...
Public Member Functions inherited from mysql::csa::Transaction_provider
virtual	~Transaction_provider ()=default
	Destructor. More...

Private Attributes
std::atomic< bool >	m_is_stopped {false}
	Variable to gracefully stop the thread. More...
Relay_log_info *	m_rli
	Pointer to channel rli object. More...
Reader_sptr	m_reader
	Shared reader object. More...
scheduler::Statistics_instance_monitor_ref	m_stat_monitor
	Statistics monitoring object. More...

Additional Inherited Members
Public Types inherited from mysql::csa::Transaction_provider
using	Common_reader_type = Relay_log_adaptive_reader

Detailed Description

Implementation of 'Transaction_provider' interface.

This implementation uses the relay log reader to read consecutive events from the relay log. Data is read from prefetched stream. Main methods are:

• start : runs asynchronous thread fetching transactions from the relay log
• stop : stops execution and blocks until thread is joined
• next : blocks until fetching the next transaction, stop or timeout when outside of transaction boundary
• is_stopped : Checks whether stop has been requested (externally or by the parent thread)

Constructor & Destructor Documentation

Sync_transaction_provider()

mysql::csa::Sync_transaction_provider::Sync_transaction_provider	(	int	instance_id,
		Relay_log_info *	rli,
		std::size_t	max_read_event_bytes,
		std::size_t	max_read_payload_bytes
	)

Parameters

instance_id	Instance (channel) id
rli	Pointer to relay log info structure
max_read_event_bytes	The maximum number of bytes in a transaction which reader can read, decode and cache
max_read_payload_bytes	The maximum number of bytes in a transaction which reader can read and cache payload

Member Function Documentation

finish()

void mysql::csa::Sync_transaction_provider::finish ( )

overridevirtual

Completes provider shutdown from the owner thread (transaction receiver).

Requires stop to have been called first; otherwise it is a no-op.

Implements mysql::csa::Transaction_provider.

is_error()

bool mysql::csa::Sync_transaction_provider::is_error ( ) const

overridevirtual

Check if provider has an error.

Returns

True in case an error occurred, false otherwise

Implements mysql::csa::Transaction_provider.

is_stopped()

bool mysql::csa::Sync_transaction_provider::is_stopped ( ) const

overridevirtual

Checks if stop has been requested.

Returns

True if stop has been requested internally (error) or externally (log wait for update)

Implements mysql::csa::Transaction_provider.

next()

Job_ptr mysql::csa::Sync_transaction_provider::next ( )

overridevirtual

Consumes the next Job, blocks until fetched.

Return values

Job	smart pointer
Empty	pointer in case stop has been requested (check with 'is_stopped') or we timed out waiting for event. In case we timed out, we return an empty pointer to wake up parent thread for a while, so that it can do some maintenance activities, such as checking status or checking statistics

Implements mysql::csa::Transaction_provider.

start()

void mysql::csa::Sync_transaction_provider::start ( )

overridevirtual

Starts asynchronous thread that decodes jobs from the stream.

Implements mysql::csa::Transaction_provider.

stop()

void mysql::csa::Sync_transaction_provider::stop ( )

overridevirtual

Stops provider and wakes blocked reader calls.

Implements mysql::csa::Transaction_provider.

Member Data Documentation

m_is_stopped

std::atomic<bool> mysql::csa::Sync_transaction_provider::m_is_stopped {false}

private

Variable to gracefully stop the thread.

m_reader

Reader_sptr mysql::csa::Sync_transaction_provider::m_reader

private

Shared reader object.

m_rli

Relay_log_info* mysql::csa::Sync_transaction_provider::m_rli

private

Pointer to channel rli object.

m_stat_monitor

scheduler::Statistics_instance_monitor_ref mysql::csa::Sync_transaction_provider::m_stat_monitor

private

Statistics monitoring object.

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

• sql/changestreams/apply/storage/relay_log/sync_transaction_provider.h
• sql/changestreams/apply/storage/relay_log/sync_transaction_provider.cpp