Recovered_xa_transactions Class Reference

This class servers as a registry for prepared XA transactions existed before server was shutdown and being resurrected during the server restart. More...

#include <xa.h>

Public Member Functions
bool	add_prepared_xa_transaction (XA_recover_txn const *prepared_xa_trn)
	Add information about prepared XA transaction into a list of XA transactions to resurrect. More...
bool	recover_prepared_xa_transactions ()
	Iterate along a list of prepared XA transactions, register every XA transaction in a cache and acquire MDL locks for every table taking part in XA transaction being resurrected. More...
MEM_ROOT *	get_allocated_memroot ()
	Get initialized MEM_ROOT. More...

Static Public Member Functions
static bool	init ()
	Initialize singleton. More...
static void	destroy ()
	Cleanup and delete singleton object. More...
static Recovered_xa_transactions &	instance ()
	Get instance of the class Recovered_xa_transactions. More...

Private Member Functions
	Recovered_xa_transactions ()

Private Attributes
std::list< XA_recover_txn *, Malloc_allocator< XA_recover_txn * > >	m_prepared_xa_trans
bool	m_mem_root_inited
MEM_ROOT	m_mem_root

Static Private Attributes
static Recovered_xa_transactions *	m_instance = nullptr

Detailed Description

This class servers as a registry for prepared XA transactions existed before server was shutdown and being resurrected during the server restart.

The class is singleton. To collect a list of XA transaction identifiers and a list of tables for that MDL locks have be acquired the method add_prepared_xa_transaction() must be called. This method is invoked by the function trx_recover_for_mysql() called by innobase_xa_recover during running of X/Open XA distributed transaction recovery procedure. After a list of XA transaction identifiers and a list of table names to be locked in MDL have been collected and the function ha_recover() has returned control flow the method recover_prepared_xa_transactions() must be called to resurrect prepared XA transactions. Separation of collecting information about prepared XA transactions from restoring XA transactions is done in order to exclude possible suspending on MDL locks inside the function dd::reset_tables_and_tablespaces() that is called right after the function ha_recover() returns control flow.

Constructor & Destructor Documentation

Recovered_xa_transactions()

Recovered_xa_transactions::Recovered_xa_transactions ( )

private

Member Function Documentation

add_prepared_xa_transaction()

bool Recovered_xa_transactions::add_prepared_xa_transaction

(

XA_recover_txn const *

prepared_xa_trn

)

Add information about prepared XA transaction into a list of XA transactions to resurrect.

Parameters

prepared_xa_trn

information about prepared XA transaction

Returns

false on success, else true

destroy()

void Recovered_xa_transactions::destroy ( )

static

Cleanup and delete singleton object.

get_allocated_memroot()

MEM_ROOT * Recovered_xa_transactions::get_allocated_memroot

(

)

Get initialized MEM_ROOT.

Returns

Pointer to a initialized MEM_ROOT.

init()

bool Recovered_xa_transactions::init ( void  )

static

Initialize singleton.

instance()

Recovered_xa_transactions & Recovered_xa_transactions::instance ( )

static

Get instance of the class Recovered_xa_transactions.

recover_prepared_xa_transactions()

bool Recovered_xa_transactions::recover_prepared_xa_transactions

(

)

Iterate along a list of prepared XA transactions, register every XA transaction in a cache and acquire MDL locks for every table taking part in XA transaction being resurrected.

Returns

false on success, else true

Member Data Documentation

m_instance

Recovered_xa_transactions * Recovered_xa_transactions::m_instance = nullptr

staticprivate

m_mem_root

MEM_ROOT Recovered_xa_transactions::m_mem_root

private

m_mem_root_inited

bool Recovered_xa_transactions::m_mem_root_inited

private

m_prepared_xa_trans

std::list<XA_recover_txn *, Malloc_allocator<XA_recover_txn *> > Recovered_xa_transactions::m_prepared_xa_trans

private

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

• sql/xa.h
• sql/xa.cc