The transaction. More...

#include <atomic>
#include <set>
#include "ha_prototypes.h"
#include "dict0types.h"
#include "trx0types.h"
#include "ut0new.h"
#include "lock0types.h"
#include "mem0mem.h"
#include "que0types.h"
#include "trx0xa.h"
#include "usr0types.h"
#include "ut0vec.h"
#include "fts0fts.h"
#include "read0read.h"
#include "sql/handler.h"
#include "srv0srv.h"
#include "trx0trx.ic"

Classes
struct	trx_lock_t
	Latching protocol for trx_lock_t::que_state. More...

struct	trx_undo_ptr_t
	The transaction handle. More...

struct	trx_rsegs_t
	Rollback segments assigned to a transaction for undo logging. More...

struct	trx_t

struct	commit_node_t
	Commit command node in a query graph. More...

class	TrxInInnoDB
	Track if a transaction is executing inside InnoDB code. More...

Macros
#define	TRX_ISO_READ_UNCOMMITTED trx_t::READ_UNCOMMITTED

#define	TRX_ISO_READ_COMMITTED trx_t::READ_COMMITTED

#define	TRX_ISO_REPEATABLE_READ trx_t::REPEATABLE_READ

#define	TRX_ISO_SERIALIZABLE trx_t::SERIALIZABLE

#define	trx_mutex_enter_low(t, first_of_two)
	Please do not use this low-level macro. More...

#define	trx_mutex_enter(t) trx_mutex_enter_low(t, false)
	Acquire the trx->mutex (and promise not to request any more). More...

#define	trx_mutex_enter_first_of_two(t) trx_mutex_enter_low(t, true)
	Acquire the trx->mutex (and indicate we might request one more). More...

#define	trx_mutex_exit(t)
	Release the trx->mutex. More...

Typedefs
typedef std::vector< ib_lock_t , ut::allocator< ib_lock_t > >	lock_pool_t

typedef std::set< dict_table_t , std::less< dict_table_t >, ut::allocator< dict_table_t * > >	trx_mod_tables_t
	Type used to store the list of tables that are modified by a given transaction. More...

Enumerations
enum	trx_rseg_type_t { TRX_RSEG_TYPE_NONE = 0 , TRX_RSEG_TYPE_REDO , TRX_RSEG_TYPE_NOREDO }

enum	commit_node_state { COMMIT_NODE_SEND = 1 , COMMIT_NODE_WAIT }
	Commit node states. More...

Functions
void	trx_set_flush_observer (trx_t trx, Flush_observer observer)
	Set flush observer for the transaction. More...

void	trx_set_detailed_error (trx_t trx, const char msg)
	Set detailed error message for the transaction. More...

void	trx_set_detailed_error_from_file (trx_t trx, FILE file)
	Set detailed error message for the transaction from a file. More...

static const dict_index_t *	trx_get_error_index (const trx_t *trx)
	Retrieves the error_info field from a trx. More...

trx_t *	trx_allocate_for_mysql (void)
	Creates a transaction object for MySQL. More...

trx_t *	trx_allocate_for_background (void)
	Creates a transaction object for background operations by the master thread. More...

void	trx_resurrect_locks (bool all)
	Resurrect table locks for resurrected transactions. More...

void	trx_clear_resurrected_table_ids ()
	Clear all resurrected table IDs. More...

void	trx_free_resurrected (trx_t *trx)
	Free and initialize a transaction object instantiated during recovery. More...

void	trx_free_for_background (trx_t *trx)
	Free a transaction that was allocated by background or user threads. More...

void	trx_free_prepared_or_active_recovered (trx_t *trx)
	At shutdown, frees a transaction object that represents either: More...

void	trx_free_for_mysql (trx_t *trx)
	Free a transaction object for MySQL. More...

void	trx_disconnect_plain (trx_t *trx)
	Disconnect a transaction from MySQL. More...

void	trx_disconnect_prepared (trx_t *trx)
	Disconnect a prepared transaction from MySQL. More...

void	trx_lists_init_at_db_start (void)
	Creates trx objects for transactions and initializes the trx list of trx_sys at database start. More...

void	trx_start_if_not_started_xa_low (trx_t *trx, bool read_write)
	Starts the transaction if it is not yet started. More...

void	trx_start_if_not_started_low (trx_t *trx, bool read_write)
	Starts the transaction if it is not yet started. More...

void	trx_start_internal_low (trx_t *trx)
	Starts a transaction for internal processing. More...

void	trx_start_internal_read_only_low (trx_t *trx)
	Starts a read-only transaction for internal processing. More...

void	trx_commit (trx_t *trx)
	Commits a transaction. More...

void	trx_commit_low (trx_t trx, mtr_t mtr)
	Commits a transaction and a mini-transaction. More...

void	trx_cleanup_at_db_startup (trx_t *trx)
	Cleans up a transaction at database startup. More...

dberr_t	trx_commit_for_mysql (trx_t *trx)
	Does the transaction commit for MySQL. More...

dberr_t	trx_prepare_for_mysql (trx_t *trx)
	Does the transaction prepare for MySQL. More...

int	trx_recover_for_mysql (XA_recover_txn txn_list, ulint len, MEM_ROOT mem_root)
	This function is used to find number of prepared transactions and their transaction objects for a recovery. More...

int	trx_recover_tc_for_mysql (Xa_state_list &xa_list)
	Find prepared transactions that are marked as prepared in TC, for recovery purposes. More...

trx_t *	trx_get_trx_by_xid (const XID *xid)
	This function is used to find one X/Open XA distributed transaction which is in the prepared state. More...

void	trx_commit_complete_for_mysql (trx_t *trx)
	If required, flushes the log to disk if we called trx_commit_for_mysql() with trx->flush_log_later == true. More...

void	trx_mark_sql_stat_end (trx_t *trx)
	Marks the latest SQL statement ended. More...

ReadView *	trx_assign_read_view (trx_t *trx)
	Assigns a read view for a consistent read query. More...

static ReadView *	trx_get_read_view (trx_t *trx)

static const ReadView *	trx_get_read_view (const trx_t *trx)

void	trx_commit_or_rollback_prepare (trx_t *trx)
	Prepares a transaction for commit/rollback. More...

commit_node_t *	trx_commit_node_create (mem_heap_t *heap)
	Creates a commit command node struct. More...

que_thr_t *	trx_commit_step (que_thr_t *thr)
	Performs an execution step for a commit type node in a query graph. More...

void	trx_print_low (FILE f, const trx_t trx, ulint max_query_len, ulint n_rec_locks, ulint n_trx_locks, ulint heap_size)
	Prints info about a transaction. More...

void	trx_print_latched (FILE f, const trx_t trx, ulint max_query_len)
	Prints info about a transaction. More...

void	trx_print (FILE f, const trx_t trx, ulint max_query_len)
	Prints info about a transaction. More...

static enum trx_dict_op_t	trx_get_dict_operation (const trx_t *trx)
	Determine if a transaction is a dictionary operation. More...

static void	trx_set_dict_operation (trx_t *trx, enum trx_dict_op_t op)
	Flag a transaction a dictionary operation. More...

static bool	trx_state_eq (const trx_t *trx, trx_state_t state)
	Determines if a transaction is in the given state. More...

bool	trx_can_be_handled_by_current_thread (const trx_t *trx)
	Determines if trx can be handled by current thread, which is when trx->mysql_thd is nullptr (a "background" trx) or equals current_thd. More...

bool	trx_can_be_handled_by_current_thread_or_is_hp_victim (const trx_t *trx)
	Determines if trx can be handled by current thread, which is when trx->mysql_thd is nullptr (a "background" trx) or equals current_thd, or is a victim being killed by HP transaction run by the current thread. More...

bool	trx_assert_started (const trx_t *trx)
	Asserts that a transaction has been started. More...

bool	trx_is_interrupted (const trx_t *trx)
	Determines if the currently running transaction has been interrupted. More...

bool	trx_is_strict (trx_t *trx)
	Determines if the currently running transaction is in strict mode. More...

bool	trx_weight_ge (const trx_t a, const trx_t b)
	Compares the "weight" (or size) of two transactions. More...

static const char *	trx_get_que_state_str (const trx_t *trx)
	Retrieves transaction's que state in a human readable string. More...

static trx_id_t	trx_get_id_for_print (const trx_t *trx)
	Retreieves the transaction ID. More...

void	trx_assign_rseg_temp (trx_t *trx)
	Assign a temp-tablespace bound rollback-segment to a transaction. More...

void	trx_pool_init ()
	Create the trx_t pool. More...

void	trx_pool_close ()
	Destroy the trx_t pool. More...

void	trx_set_rw_mode (trx_t *trx)
	Set the transaction as a read-write transaction if it is not already tagged as such. More...

static const trx_t *	trx_arbitrate (const trx_t requestor, const trx_t holder)

static bool	trx_is_high_priority (const trx_t *trx)

void	trx_kill_blocking (trx_t *trx)
	If this is a high priority transaction, kill all transactions that are blocking this transaction from acquiring locks. More...

static uint64_t	trx_immutable_id (const trx_t *trx)
	Provides an id of the transaction which does not change over time. More...

static bool	trx_is_rseg_updated (const trx_t *trx)
	Check if redo/noredo rseg is modified for insert/update. More...

static std::chrono::seconds	trx_lock_wait_timeout_get (const trx_t *t)
	Transactions that aren't started by the MySQL server don't set the trx_t::mysql_thd field. More...

static bool	trx_is_autocommit_non_locking (const trx_t *t)
	Determine if the transaction is a non-locking autocommit select (implied read-only). More...

static void	check_trx_state (const trx_t *t)
	Check transaction state. More...

static void	assert_trx_in_rw_list (const trx_t *t)
	Assert that the transaction is in the trx_sys_t::rw_trx_list. More...

static void	assert_trx_is_free (const trx_t *t)
	Check if transaction is free so that it can be re-initialized. More...

static void	assert_trx_is_inactive (const trx_t *t)
	Check if transaction is in-active so that it can be freed and put back to transaction pool. More...

static void	assert_trx_nonlocking_or_in_list (const trx_t *t)
	Assert that an autocommit non-locking select cannot be in the rw_trx_list and that it is a read-only transaction. More...

static bool	trx_is_ac_nl_ro (const trx_t *t)
	Determine if the transaction is a non-locking autocommit select with an explicit check for the read-only status. More...

static void	trx_reference (trx_t *trx)
	Increase the reference count. More...

static void	trx_release_reference (trx_t *trx)
	Release the transaction. More...

static bool	trx_is_referenced (const trx_t *t)
	Check if the transaction is being referenced. More...

static uint64_t	TRX_WEIGHT (const trx_t *t)
	Calculates the "weight" of a transaction. More...

static void	trx_start_if_not_started_xa (trx_t *t, bool rw, ut::Location loc)

static void	trx_start_if_not_started (trx_t *t, bool rw, ut::Location l)

static void	trx_start_internal (trx_t *t, ut::Location loc)

static void	trx_start_internal_read_only (trx_t *t, ut::Location loc)

bool	trx_was_started (const trx_t *trx)
	Check if transaction was started. More...

bool	trx_is_started (const trx_t *trx)
	Check if transaction is started. More...

bool	trx_mutex_own (const trx_t *trx)
	Test if trx->mutex is owned by the current thread. More...

void	trx_before_mutex_enter (const trx_t *trx, bool allow_another)
	Verifies the invariants and records debug state related to latching rules. More...

void	trx_before_mutex_exit (const trx_t *trx)
	Verifies the invariants and records debug state related to latching rules. More...

bool	trx_is_mysql_xa (const trx_t *trx)
	Check if transaction is internal XA transaction. More...

void	trx_sys_update_binlog_position (trx_t *trx)
	Update transaction binlog file name and position from session THD. More...

bool	trx_is_prepared_in_tc (trx_t const *trx)
	Checks whether or not the transaction has been marked as prepared in TC. More...

dberr_t	trx_set_prepared_in_tc_for_mysql (trx_t *trx)
	Does the 2nd phase of an XA transaction prepare for MySQL. More...

Variables
std::vector< std::pair< trx_id_t, table_id_t > >	to_rollback_trx_tables

sess_t *	trx_dummy_sess
	Dummy session used currently in MySQL interface. More...

constexpr uint32_t	TRX_QUE_STATE_STR_MAX_LEN = 12

Detailed Description

The transaction.

Created 3/26/1996 Heikki Tuuri

Macro Definition Documentation

◆ TRX_ISO_READ_COMMITTED

#define TRX_ISO_READ_COMMITTED trx_t::READ_COMMITTED

◆ TRX_ISO_READ_UNCOMMITTED

#define TRX_ISO_READ_UNCOMMITTED trx_t::READ_UNCOMMITTED

◆ TRX_ISO_REPEATABLE_READ

#define TRX_ISO_REPEATABLE_READ trx_t::REPEATABLE_READ

◆ TRX_ISO_SERIALIZABLE

#define TRX_ISO_SERIALIZABLE trx_t::SERIALIZABLE

◆ trx_mutex_enter

#define trx_mutex_enter ( t ) trx_mutex_enter_low(t, false)

Acquire the trx->mutex (and promise not to request any more).

◆ trx_mutex_enter_first_of_two

#define trx_mutex_enter_first_of_two ( t ) trx_mutex_enter_low(t, true)

Acquire the trx->mutex (and indicate we might request one more).

◆ trx_mutex_enter_low

#define trx_mutex_enter_low	(	t,
		first_of_two
	)

Value:

  do {                                             \
    ut_ad(!trx_mutex_own(t));                      \
    ut_d(trx_before_mutex_enter(t, first_of_two)); \
    mutex_enter(&t->mutex);                        \
  } while (0)

Please do not use this low-level macro.

Use trx_mutex_enter(t) instead. In rare cases where you need to take two trx->mutex-es, take the first one using trx_mutex_enter_first_of_two(t1), and the second one with trx_mutex(2)

◆ trx_mutex_exit

#define trx_mutex_exit ( t )

Value:

  do {                              \
    ut_ad(trx_mutex_own(t));        \
    ut_d(trx_before_mutex_exit(t)); \
    mutex_exit(&t->mutex);          \
  } while (0)

Release the trx->mutex.

Typedef Documentation

◆ lock_pool_t

typedef std::vector<ib_lock_t *, ut::allocator<ib_lock_t *> > lock_pool_t

◆ trx_mod_tables_t

typedef std::set<dict_table_t *, std::less<dict_table_t *>, ut::allocator<dict_table_t *> > trx_mod_tables_t

Type used to store the list of tables that are modified by a given transaction.

We store pointers to the table objects in memory because we know that a table object will not be destroyed while a transaction that modified it is running.

Enumeration Type Documentation

◆ commit_node_state

enum commit_node_state

Commit node states.

Enumerator
COMMIT_NODE_SEND	about to send a commit signal to the transaction
COMMIT_NODE_WAIT	commit signal sent to the transaction, waiting for completion

◆ trx_rseg_type_t

enum trx_rseg_type_t

Enumerator
TRX_RSEG_TYPE_NONE	void rollback segment type.
TRX_RSEG_TYPE_REDO	redo rollback segment.
TRX_RSEG_TYPE_NOREDO	non-redo rollback segment.

Function Documentation

◆ assert_trx_in_rw_list()

static void assert_trx_in_rw_list ( const trx_t * t )

inlinestatic

Assert that the transaction is in the trx_sys_t::rw_trx_list.

◆ assert_trx_is_free()

static void assert_trx_is_free ( const trx_t * t )

inlinestatic

Check if transaction is free so that it can be re-initialized.

Parameters

t	transaction handle

◆ assert_trx_is_inactive()

static void assert_trx_is_inactive ( const trx_t * t )

inlinestatic

Check if transaction is in-active so that it can be freed and put back to transaction pool.

Parameters

t	transaction handle

◆ assert_trx_nonlocking_or_in_list()

static void assert_trx_nonlocking_or_in_list ( const trx_t * t )

inlinestatic

Assert that an autocommit non-locking select cannot be in the rw_trx_list and that it is a read-only transaction.

The transaction must be in the mysql_trx_list.

◆ check_trx_state()

static void check_trx_state ( const trx_t * t )

inlinestatic

Check transaction state.

◆ trx_allocate_for_background()

trx_t * trx_allocate_for_background ( void )

Creates a transaction object for background operations by the master thread.

Returns: own: transaction object

◆ trx_allocate_for_mysql()

trx_t * trx_allocate_for_mysql ( void )

Creates a transaction object for MySQL.

Returns: own: transaction object

◆ trx_arbitrate()

static const trx_t * trx_arbitrate	(	const trx_t *	requestor,
		const trx_t *	holder
	)

inlinestatic

Parameters

[in]	requestor	Transaction requesting the lock
[in]	holder	Transaction holding the lock

Returns: the transaction that will be rolled back, null don't care

◆ trx_assert_started()

bool trx_assert_started ( const trx_t * trx )

Asserts that a transaction has been started.

The caller must hold trx_sys->mutex.

Returns: true if started in: transaction

The caller must hold trx_sys->mutex.

Returns: true if started

Parameters

trx	in: transaction

◆ trx_assign_read_view()

ReadView * trx_assign_read_view ( trx_t * trx )

Assigns a read view for a consistent read query.

All the consistent reads within the same transaction will get the same read view, which is created when this function is first called for a new started transaction. in: active transaction

All the consistent reads within the same transaction will get the same read view, which is created when this function is first called for a new started transaction.

Returns: consistent read view

Parameters

trx	in/out: active transaction

◆ trx_assign_rseg_temp()

void trx_assign_rseg_temp ( trx_t * trx )

Assign a temp-tablespace bound rollback-segment to a transaction.

Parameters

[in,out] trx transaction that involves write to temp-table.

◆ trx_before_mutex_enter()

void trx_before_mutex_enter	(	const trx_t *	trx,
		bool	allow_another
	)

Verifies the invariants and records debug state related to latching rules.

Called during trx_mutex_enter before the actual mutex acquisition.

Parameters

[in]	trx	The transaction for which trx_mutex_enter(trx) is called
[in]	allow_another	If false, then no further calls to trx_mutex_enter are allowed, until trx_mutex_exit(). If true, then this must be the first trx acquisition and we will allow one more.

◆ trx_before_mutex_exit()

void trx_before_mutex_exit ( const trx_t * trx )

Verifies the invariants and records debug state related to latching rules.

Called during trx_mutex_exit before the actual mutex release.

Parameters

[in] trx The transaction for which trx_mutex_exit(trx) is called

◆ trx_can_be_handled_by_current_thread()

bool trx_can_be_handled_by_current_thread ( const trx_t * trx )

Determines if trx can be handled by current thread, which is when trx->mysql_thd is nullptr (a "background" trx) or equals current_thd.

Parameters

[in] trx The transaction to check

Returns: true iff current thread can handle the transaction

◆ trx_can_be_handled_by_current_thread_or_is_hp_victim()

bool trx_can_be_handled_by_current_thread_or_is_hp_victim ( const trx_t * trx )

Determines if trx can be handled by current thread, which is when trx->mysql_thd is nullptr (a "background" trx) or equals current_thd, or is a victim being killed by HP transaction run by the current thread.

Parameters

[in] trx The transaction to check

Returns: true iff current thread can handle the transaction

◆ trx_cleanup_at_db_startup()

void trx_cleanup_at_db_startup ( trx_t * trx )

Cleans up a transaction at database startup.

The cleanup is needed if the transaction already got to the middle of a commit when the database crashed, and we cannot roll it back. in: transaction

The cleanup is needed if the transaction already got to the middle of a commit when the database crashed, and we cannot roll it back.

Parameters

trx	in: transaction

◆ trx_clear_resurrected_table_ids()

void trx_clear_resurrected_table_ids ( )

Clear all resurrected table IDs.

Needs to be called after all tables locks are resurrected.

◆ trx_commit()

void trx_commit ( trx_t * trx )

Commits a transaction.

in/out: transaction

Parameters

trx	in/out: transaction

◆ trx_commit_complete_for_mysql()

void trx_commit_complete_for_mysql ( trx_t * trx )

If required, flushes the log to disk if we called trx_commit_for_mysql() with trx->flush_log_later == true.

in/out: transaction

Parameters

trx	in/out: transaction

◆ trx_commit_for_mysql()

dberr_t trx_commit_for_mysql ( trx_t * trx )

Does the transaction commit for MySQL.

Returns: DB_SUCCESS or error number in/out: transaction; DB_SUCCESS or error number

Parameters

trx	in/out: transaction

◆ trx_commit_low()

void trx_commit_low	(	trx_t *	trx,
		mtr_t *	mtr
	)

Commits a transaction and a mini-transaction.

Parameters

[in,out]	trx	Transaction
[in,out]	mtr	Mini-transaction (will be committed), or null if trx made no modifications

◆ trx_commit_node_create()

commit_node_t * trx_commit_node_create ( mem_heap_t * heap )

Creates a commit command node struct.

Returns: own: commit node struct in: mem heap where created; own: commit node struct

Parameters

heap	in: mem heap where created

◆ trx_commit_or_rollback_prepare()

void trx_commit_or_rollback_prepare ( trx_t * trx )

Prepares a transaction for commit/rollback.

in/out: transaction

Parameters

trx	in/out: transaction

◆ trx_commit_step()

que_thr_t * trx_commit_step ( que_thr_t * thr )

Performs an execution step for a commit type node in a query graph.

Returns: query thread to run next, or NULL in: query thread; query thread to run next, or NULL

Parameters

thr	in: query thread

◆ trx_disconnect_plain()

void trx_disconnect_plain ( trx_t * trx )

inline

Disconnect a transaction from MySQL.

Parameters

[in,out] trx transaction

◆ trx_disconnect_prepared()

void trx_disconnect_prepared ( trx_t * trx )

Disconnect a prepared transaction from MySQL.

Parameters

[in,out] trx transaction

◆ trx_free_for_background()

void trx_free_for_background ( trx_t * trx )

Free a transaction that was allocated by background or user threads.

Parameters

[in,out] trx transaction object to free

◆ trx_free_for_mysql()

void trx_free_for_mysql ( trx_t * trx )

Free a transaction object for MySQL.

Parameters

[in,out] trx transaction

◆ trx_free_prepared_or_active_recovered()

void trx_free_prepared_or_active_recovered ( trx_t * trx )

At shutdown, frees a transaction object that represents either:

a PREPARED transaction,
or a recovered ACTIVE transaction.
Parameters

[in,out] trx transaction object to free

◆ trx_free_resurrected()

void trx_free_resurrected ( trx_t * trx )

Free and initialize a transaction object instantiated during recovery.

Parameters

[in,out] trx transaction object to free and initialize

◆ trx_get_dict_operation()

static enum trx_dict_op_t trx_get_dict_operation ( const trx_t * trx )

inlinestatic

Determine if a transaction is a dictionary operation.

Returns: dictionary operation mode in: transaction

◆ trx_get_error_index()

static const dict_index_t * trx_get_error_index ( const trx_t * trx )

inlinestatic

Retrieves the error_info field from a trx.

Returns: the error index in: trx object

◆ trx_get_id_for_print()

static trx_id_t trx_get_id_for_print ( const trx_t * trx )

inlinestatic

Retreieves the transaction ID.

In a given point in time it is guaranteed that IDs of the running transactions are unique. The values returned by this function for readonly transactions may be reused, so a subsequent RO transaction may get the same ID as a RO transaction that existed in the past. The values returned by this function should be used for printing purposes only.

Parameters

[in] trx transaction whose id to retrieve

Returns: transaction id

◆ trx_get_que_state_str()

static const char * trx_get_que_state_str ( const trx_t * trx )

inlinestatic

Retrieves transaction's que state in a human readable string.

The string should not be free()'d or modified.

Returns: string in the data segment in: transaction

◆ trx_get_read_view() [1/2]

static const ReadView * trx_get_read_view ( const trx_t * trx )

inlinestatic

Returns: the transaction's read view or NULL if one not assigned.

◆ trx_get_read_view() [2/2]

static ReadView * trx_get_read_view ( trx_t * trx )

inlinestatic

Returns: the transaction's read view or NULL if one not assigned.

◆ trx_get_trx_by_xid()

trx_t * trx_get_trx_by_xid ( const XID * xid )

This function is used to find one X/Open XA distributed transaction which is in the prepared state.

Parameters

[in] xid X/Open XA transaction identifier

Returns: trx or NULL; on match, the trx->xid will be invalidated; note that the trx may have been committed

◆ trx_immutable_id()

static uint64_t trx_immutable_id ( const trx_t * trx )

inlinestatic

Provides an id of the transaction which does not change over time.

Contrast this with trx->id and trx_get_id_for_print(trx) which change value once a transaction can no longer be treated as read-only and becomes read-write.

Parameters

[in] trx The transaction for which you want an immutable id

Returns: the transaction's immutable id

◆ trx_is_ac_nl_ro()

static bool trx_is_ac_nl_ro ( const trx_t * t )

inlinestatic

Determine if the transaction is a non-locking autocommit select with an explicit check for the read-only status.

Parameters

t	transaction

Returns: true if non-locking autocommit read-only transaction.

◆ trx_is_autocommit_non_locking()

static bool trx_is_autocommit_non_locking ( const trx_t * t )

inlinestatic

Determine if the transaction is a non-locking autocommit select (implied read-only).

Parameters

t	transaction

Returns: true if non-locking autocommit select transaction.

◆ trx_is_high_priority()

static bool trx_is_high_priority ( const trx_t * trx )

inlinestatic

Parameters

[in] trx Transaction to check

Returns: true if the transaction is a high priority transaction.

◆ trx_is_interrupted()

bool trx_is_interrupted ( const trx_t * trx )

Determines if the currently running transaction has been interrupted.

Returns: true if interrupted in: transaction; true if interrupted

Parameters

trx	in: transaction

◆ trx_is_mysql_xa()

bool trx_is_mysql_xa ( const trx_t * trx )

Check if transaction is internal XA transaction.

Parameters

[in] trx transaction

Returns: true, iff internal XA transaction.

◆ trx_is_prepared_in_tc()

bool trx_is_prepared_in_tc ( trx_t const * trx )

Checks whether or not the transaction has been marked as prepared in TC.

Parameters

[in] trx the transaction

Returns: true if the transaction is marked as prepared in TC, false otherwise.

◆ trx_is_referenced()

static bool trx_is_referenced ( const trx_t * t )

inlinestatic

Check if the transaction is being referenced.

◆ trx_is_rseg_updated()

static bool trx_is_rseg_updated ( const trx_t * trx )

inlinestatic

Check if redo/noredo rseg is modified for insert/update.

Parameters

[in] trx Transaction to check

◆ trx_is_started()

bool trx_is_started ( const trx_t * trx )

inline

Check if transaction is started.

Parameters

[in] trx Transaction whose state we need to check

Returns: true if transaction is in state started

◆ trx_is_strict()

bool trx_is_strict ( trx_t * trx )

Determines if the currently running transaction is in strict mode.

Returns: true if strict in: transaction; true if strict

Parameters

trx	in: transaction

◆ trx_kill_blocking()

void trx_kill_blocking ( trx_t * trx )

If this is a high priority transaction, kill all transactions that are blocking this transaction from acquiring locks.

Parameters

[in,out] trx High priority transaction

Kill the transactions in the lock acquisition order old -> new.

◆ trx_lists_init_at_db_start()

void trx_lists_init_at_db_start ( void )

Creates trx objects for transactions and initializes the trx list of trx_sys at database start.

Rollback segment and undo log lists must already exist when this function is called, because the lists of transactions to be rolled back or cleaned up are built based on the undo log lists.

Rollback segments and undo log lists must already exist when this function is called, because the lists of transactions to be rolled back or cleaned up are built based on the undo log lists.

◆ trx_lock_wait_timeout_get()

static std::chrono::seconds trx_lock_wait_timeout_get ( const trx_t * t )

inlinestatic

Transactions that aren't started by the MySQL server don't set the trx_t::mysql_thd field.

For such transactions we set the lock wait timeout to 0 instead of the user configured value that comes from innodb_lock_wait_timeout via trx_t::mysql_thd.

Parameters

t	transaction

Returns: lock wait timeout in seconds

◆ trx_mark_sql_stat_end()

void trx_mark_sql_stat_end ( trx_t * trx )

Marks the latest SQL statement ended.

in: trx handle

Parameters

trx	in: trx handle

◆ trx_mutex_own()

bool trx_mutex_own ( const trx_t * trx )

inline

Test if trx->mutex is owned by the current thread.

◆ trx_pool_close()

void trx_pool_close ( )

Destroy the trx_t pool.

◆ trx_pool_init()

void trx_pool_init ( )

Create the trx_t pool.

◆ trx_prepare_for_mysql()

dberr_t trx_prepare_for_mysql ( trx_t * trx )

Does the transaction prepare for MySQL.

Parameters

[in,out] trx Transaction instance to prepare

◆ trx_print()

void trx_print	(	FILE *	f,
		const trx_t *	trx,
		ulint	max_query_len
	)

Prints info about a transaction.

Acquires and releases lock_sys exclusive global latch and trx_sys->mutex.

Parameters

[in]	f	output stream
[in]	trx	transaction
[in]	max_query_len	max query length to print, must be positive

◆ trx_print_latched()

void trx_print_latched	(	FILE *	f,
		const trx_t *	trx,
		ulint	max_query_len
	)

Prints info about a transaction.

The caller must hold lock_sys exclusive global latch and trx_sys->mutex.

Parameters

[in]	f	output stream
[in]	trx	transaction
[in]	max_query_len	max query length to print, must be positive

◆ trx_print_low()

void trx_print_low	(	FILE *	f,
		const trx_t *	trx,
		ulint	max_query_len,
		ulint	n_rec_locks,
		ulint	n_trx_locks,
		ulint	heap_size
	)

Prints info about a transaction.

Caller must hold trx_sys->mutex. in: mem_heap_get_size(trx->lock.lock_heap)

Caller must hold trx_sys->mutex.

Parameters

f	in: output stream
trx	in: transaction
max_query_len	in: max query length to print, must be positive
n_rec_locks	in: lock_number_of_rows_locked(&trx->lock)
n_trx_locks	in: length of trx->lock.trx_locks
heap_size	in: mem_heap_get_size(trx->lock.lock_heap)

◆ trx_recover_for_mysql()

int trx_recover_for_mysql	(	XA_recover_txn *	txn_list,
		ulint	len,
		MEM_ROOT *	mem_root
	)

This function is used to find number of prepared transactions and their transaction objects for a recovery.

Returns: number of prepared transactions in: memory for table names; number of prepared transactions stored in xid_list

Parameters

txn_list	in/out: prepared transactions
len	in: number of slots in xid_list
mem_root	in: memory for table names

◆ trx_recover_tc_for_mysql()

int trx_recover_tc_for_mysql ( Xa_state_list & xa_list )

Find prepared transactions that are marked as prepared in TC, for recovery purposes.

Parameters

[in,out] xa_list prepared transactions state

Returns: 0 if successful or error number

◆ trx_reference()

static void trx_reference ( trx_t * trx )

inlinestatic

Increase the reference count.

If the transaction is in state TRX_STATE_COMMITTED_IN_MEMORY then the transaction is considered committed and the reference count is not incremented.

Parameters

trx	Transaction that is being referenced

◆ trx_release_reference()

static void trx_release_reference ( trx_t * trx )

inlinestatic

Release the transaction.

Decrease the reference count.

Parameters

trx	Transaction that is being released

◆ trx_resurrect_locks()

void trx_resurrect_locks ( bool all )

Resurrect table locks for resurrected transactions.

Parameters

[in] all false: resurrect locks for dictionary transactions, true : resurrect locks for all transactions.

◆ trx_set_detailed_error()

void trx_set_detailed_error	(	trx_t *	trx,
		const char *	msg
	)

Set detailed error message for the transaction.

Parameters

[in]	trx	Transaction struct
[in]	msg	Detailed error message

◆ trx_set_detailed_error_from_file()

void trx_set_detailed_error_from_file	(	trx_t *	trx,
		FILE *	file
	)

Set detailed error message for the transaction from a file.

Note that the file is rewinded before reading from it. in: file to read message from

Note that the file is rewinded before reading from it.

Parameters

trx	in: transaction struct
file	in: file to read message from

◆ trx_set_dict_operation()

static void trx_set_dict_operation	(	trx_t *	trx,
		enum trx_dict_op_t	op
	)

inlinestatic

Flag a transaction a dictionary operation.

Parameters

[in,out]	trx	transaction
[in]	op	operation, not TRX_DICT_OP_NONE

◆ trx_set_flush_observer()

void trx_set_flush_observer	(	trx_t *	trx,
		Flush_observer *	observer
	)

Set flush observer for the transaction.

Parameters

[in,out]	trx	transaction struct
[in]	observer	flush observer

◆ trx_set_prepared_in_tc_for_mysql()

dberr_t trx_set_prepared_in_tc_for_mysql ( trx_t * trx )

Does the 2nd phase of an XA transaction prepare for MySQL.

Parameters

[in,out] trx Transaction instance to finish prepare

Returns: DB_SUCCESS or error number

◆ trx_set_rw_mode()

void trx_set_rw_mode ( trx_t * trx )

Set the transaction as a read-write transaction if it is not already tagged as such.

Parameters

[in,out] trx Transaction that needs to be "upgraded" to RW from RO

Read-only transactions that are writing to temporary tables are assigned an ID and a rollback segment but are not added to the trx read-write list because their updates should not be visible to other transactions and therefore their changes can be ignored by by MVCC.

Parameters

trx	in/out: transaction that is RW

◆ trx_start_if_not_started()

static void trx_start_if_not_started	(	trx_t *	t,
		bool	rw,
		ut::Location	l
	)

inlinestatic

◆ trx_start_if_not_started_low()

void trx_start_if_not_started_low	(	trx_t *	trx,
		bool	read_write
	)

Starts the transaction if it is not yet started.

Parameters

[in]	trx	Transaction
[in]	read_write	True if read write transaction

◆ trx_start_if_not_started_xa()

static void trx_start_if_not_started_xa	(	trx_t *	t,
		bool	rw,
		ut::Location	loc
	)

inlinestatic

◆ trx_start_if_not_started_xa_low()

void trx_start_if_not_started_xa_low	(	trx_t *	trx,
		bool	read_write
	)

Starts the transaction if it is not yet started.

Parameters

[in,out]	trx	Transaction
[in]	read_write	True if read write transaction

◆ trx_start_internal()

static void trx_start_internal	(	trx_t *	t,
		ut::Location	loc
	)

inlinestatic

◆ trx_start_internal_low()

void trx_start_internal_low ( trx_t * trx )

Starts a transaction for internal processing.

in/out: transaction

Parameters

trx	in/out: transaction

◆ trx_start_internal_read_only()

static void trx_start_internal_read_only	(	trx_t *	t,
		ut::Location	loc
	)

inlinestatic

◆ trx_start_internal_read_only_low()

void trx_start_internal_read_only_low ( trx_t * trx )

Starts a read-only transaction for internal processing.

Parameters

[in,out] trx transaction to be started

◆ trx_state_eq()

static bool trx_state_eq	(	const trx_t *	trx,
		trx_state_t	state
	)

inlinestatic

Determines if a transaction is in the given state.

The caller must hold trx_sys->mutex, or it must be the thread that is serving a running transaction. A running RW transaction must be in trx_sys->rw_trx_list.

Parameters

[in]	trx	Transaction.
[in]	state	State.

Returns: true if trx->state == state

◆ trx_sys_update_binlog_position()

void trx_sys_update_binlog_position ( trx_t * trx )

Update transaction binlog file name and position from session THD.

Parameters

[in,out] trx current transaction.

◆ trx_was_started()

bool trx_was_started ( const trx_t * trx )

inline

Check if transaction was started.

Note, that after the check situation might have already been changed (and note that holding the trx_sys->mutex does not prevent state transitions for read-only transactions).

Parameters

[in] trx Transaction whose state we need to check

Returns: true if transaction is in state started

◆ TRX_WEIGHT()

static uint64_t TRX_WEIGHT ( const trx_t * t )

inlinestatic

Calculates the "weight" of a transaction.

The weight of one transaction is estimated as the number of altered rows + the number of locked rows.

Parameters

t	transaction

Returns: transaction weight

◆ trx_weight_ge()

bool trx_weight_ge	(	const trx_t *	a,
		const trx_t *	b
	)

Compares the "weight" (or size) of two transactions.

Transactions that have edited non-transactional tables are considered heavier than ones that have not.

Returns: true if weight(a) >= weight(b) in: the transaction to be compared

Transactions that have edited non-transactional tables are considered heavier than ones that have not.

Returns: true if weight(a) >= weight(b)

Parameters

a	in: transaction to be compared
b	in: transaction to be compared

Variable Documentation

◆ to_rollback_trx_tables

std::vector<std::pair<trx_id_t, table_id_t> > to_rollback_trx_tables

extern

◆ trx_dummy_sess

sess_t* trx_dummy_sess

extern

Dummy session used currently in MySQL interface.

◆ TRX_QUE_STATE_STR_MAX_LEN

constexpr uint32_t TRX_QUE_STATE_STR_MAX_LEN = 12

constexpr

Classes

Macros

Typedefs

Enumerations

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ TRX_ISO_READ_COMMITTED

◆ TRX_ISO_READ_UNCOMMITTED

◆ TRX_ISO_REPEATABLE_READ

◆ TRX_ISO_SERIALIZABLE

◆ trx_mutex_enter

◆ trx_mutex_enter_first_of_two

◆ trx_mutex_enter_low

◆ trx_mutex_exit

Typedef Documentation

◆ lock_pool_t

◆ trx_mod_tables_t

Enumeration Type Documentation

◆ commit_node_state

◆ trx_rseg_type_t

Function Documentation

◆ assert_trx_in_rw_list()

◆ assert_trx_is_free()

◆ assert_trx_is_inactive()

◆ assert_trx_nonlocking_or_in_list()

◆ check_trx_state()

◆ trx_allocate_for_background()

◆ trx_allocate_for_mysql()

◆ trx_arbitrate()

◆ trx_assert_started()

◆ trx_assign_read_view()

◆ trx_assign_rseg_temp()

◆ trx_before_mutex_enter()

◆ trx_before_mutex_exit()

◆ trx_can_be_handled_by_current_thread()

◆ trx_can_be_handled_by_current_thread_or_is_hp_victim()

◆ trx_cleanup_at_db_startup()

◆ trx_clear_resurrected_table_ids()

◆ trx_commit()

◆ trx_commit_complete_for_mysql()

◆ trx_commit_for_mysql()

◆ trx_commit_low()

◆ trx_commit_node_create()

◆ trx_commit_or_rollback_prepare()

◆ trx_commit_step()

◆ trx_disconnect_plain()

◆ trx_disconnect_prepared()

◆ trx_free_for_background()

◆ trx_free_for_mysql()

◆ trx_free_prepared_or_active_recovered()

◆ trx_free_resurrected()

◆ trx_get_dict_operation()

◆ trx_get_error_index()

◆ trx_get_id_for_print()

◆ trx_get_que_state_str()

◆ trx_get_read_view() [1/2]

◆ trx_get_read_view() [2/2]

◆ trx_get_trx_by_xid()

◆ trx_immutable_id()

◆ trx_is_ac_nl_ro()

◆ trx_is_autocommit_non_locking()

◆ trx_is_high_priority()

◆ trx_is_interrupted()

◆ trx_is_mysql_xa()

◆ trx_is_prepared_in_tc()

◆ trx_is_referenced()

◆ trx_is_rseg_updated()

◆ trx_is_started()

◆ trx_is_strict()

◆ trx_kill_blocking()

◆ trx_lists_init_at_db_start()

◆ trx_lock_wait_timeout_get()

◆ trx_mark_sql_stat_end()

◆ trx_mutex_own()

◆ trx_pool_close()

◆ trx_pool_init()

◆ trx_prepare_for_mysql()

◆ trx_print()