trx0sys.ic File Reference

Transaction system. More...

#include "data0type.h"
#include "srv0srv.h"
#include "trx0trx.h"
#include "mtr0log.h"
#include "my_dbug.h"

Typedefs
typedef byte	trx_sysf_rseg_t

Functions
void	trx_sys_write_max_trx_id (void)
	Writes the value of max_trx_id to the file based trx system header. More...
static bool	trx_sys_hdr_page (const page_id_t &page_id)
	Checks if a page address is the trx sys header page. More...
static trx_sysf_t *	trx_sysf_get (mtr_t *mtr)
	Gets a pointer to the transaction system header and x-latches its page. More...
static space_id_t	trx_sysf_rseg_get_space (trx_sysf_t *sys_header, ulint slot, mtr_t *mtr)
	Gets the space of the nth rollback segment slot in the trx system file copy. More...
static page_no_t	trx_sysf_rseg_get_page_no (trx_sysf_t *sys_header, ulint slot, mtr_t *mtr)
	Gets the page number of the nth rollback segment slot in the trx system header. More...
static void	trx_sysf_rseg_set_space (trx_sysf_t *sys_header, ulint slot, space_id_t space, mtr_t *mtr)
	Sets the space id of the nth rollback segment slot in the trx system file copy. More...
static void	trx_sysf_rseg_set_page_no (trx_sysf_t *sys_header, ulint slot, page_no_t page_no, mtr_t *mtr)
	Sets the page number of the nth rollback segment slot in the trx system header. More...
static void	trx_write_trx_id (byte *ptr, trx_id_t id)
	Writes a trx id to an index page. More...
static trx_id_t	trx_read_trx_id (const byte *ptr)
	Reads a trx id from an index page. More...
static trx_t *	trx_rw_is_active (trx_id_t trx_id, bool do_ref_count)
trx_id_t	trx_sys_get_trx_id_write_margin ()
trx_id_t	trx_sys_allocate_trx_id_or_no ()
	Allocates a new transaction id or transaction number. More...
trx_id_t	trx_sys_allocate_trx_id ()
	Allocates a new transaction id (for trx->id). More...
trx_id_t	trx_sys_allocate_trx_no ()
	Allocates a new transaction number (for trx->no). More...
static trx_id_t	trx_get_serialisation_min_trx_no (void)
	Reads trx->no up to which all transactions have been serialised. More...
trx_id_t	trx_sys_get_next_trx_id_or_no ()
	Retrieves a next value that will be allocated if trx_sys_allocate_trx_id() or trx_sys_allocate_trx_id_trx_no() was called. More...
static bool	trx_sys_need_rollback ()
	Determine if there are incomplete transactions in the system. More...
static void	trx_sys_rw_trx_add (trx_t *trx)

Variables
constexpr uint32_t	TRX_SYS_RSEG_SPACE = 0
	space where the segment header is placed; starting with MySQL/InnoDB 5.1.7, this is UNIV_UNDEFINED if the slot is unused More...
constexpr uint32_t	TRX_SYS_RSEG_PAGE_NO = 4
	page number where the segment header is placed; this is FIL_NULL if the slot is unused More...
constexpr uint32_t	TRX_SYS_RSEG_SLOT_SIZE = 8

Detailed Description

Transaction system.

Created 3/26/1996 Heikki Tuuri

Typedef Documentation

trx_sysf_rseg_t

typedef byte trx_sysf_rseg_t

Function Documentation

trx_get_serialisation_min_trx_no()

static trx_id_t trx_get_serialisation_min_trx_no ( void  )

inlinestatic

Reads trx->no up to which all transactions have been serialised.

Returns

minimum value which is still possibly not serialised

trx_read_trx_id()

static trx_id_t trx_read_trx_id ( const byte *  ptr )

inlinestatic

Reads a trx id from an index page.

In case that the id size changes in some future version, this function should be used instead of mach_read_...

Returns

id

Parameters

ptr	in: pointer to memory from where to read

trx_rw_is_active()

static trx_t * trx_rw_is_active ( trx_id_t  trx_id, bool  do_ref_count  )

inlinestatic

trx_sys_allocate_trx_id()

trx_id_t trx_sys_allocate_trx_id ( )

inline

Allocates a new transaction id (for trx->id).

Before calling, the trx_sys_mutex must be acquired.

Returns

new, allocated trx id

trx_sys_allocate_trx_id_or_no()

trx_id_t trx_sys_allocate_trx_id_or_no ( )

inline

Allocates a new transaction id or transaction number.

Returns

new, allocated trx id or trx no

trx_sys_allocate_trx_no()

trx_id_t trx_sys_allocate_trx_no ( )

inline

Allocates a new transaction number (for trx->no).

Before calling, the trx_sys_serialisation_mutex must be acquired.

Returns

new, allocated trx no

trx_sys_get_next_trx_id_or_no()

trx_id_t trx_sys_get_next_trx_id_or_no ( )

inline

Retrieves a next value that will be allocated if trx_sys_allocate_trx_id() or trx_sys_allocate_trx_id_trx_no() was called.

Returns

the next trx->id or trx->no that will be allocated

trx_sys_get_trx_id_write_margin()

trx_id_t trx_sys_get_trx_id_write_margin ( )

inline

trx_sys_hdr_page()

static bool trx_sys_hdr_page ( const page_id_t &  page_id )

inlinestatic

Checks if a page address is the trx sys header page.

Parameters

[in]

page_id

page id

Returns

true if trx sys header page

trx_sys_need_rollback()

static bool trx_sys_need_rollback ( )

inlinestatic

Determine if there are incomplete transactions in the system.

Returns

whether incomplete transactions need rollback

trx_sys_rw_trx_add()

static void trx_sys_rw_trx_add ( trx_t *  trx )

inlinestatic

trx_sys_write_max_trx_id()

void trx_sys_write_max_trx_id

(

void

)

Writes the value of max_trx_id to the file based trx system header.

trx_sysf_get()

static trx_sysf_t * trx_sysf_get ( mtr_t *  mtr )

inlinestatic

Gets a pointer to the transaction system header and x-latches its page.

Returns

pointer to system header, page x-latched.

Parameters

mtr

in: mtr

trx_sysf_rseg_get_page_no()

static page_no_t trx_sysf_rseg_get_page_no ( trx_sysf_t *  sys_header, ulint  slot, mtr_t *  mtr  )

inlinestatic

Gets the page number of the nth rollback segment slot in the trx system header.

Returns

page number, FIL_NULL if slot unused

Parameters

sys_header	in: trx system header
slot	in: slot index == rseg id
mtr	in: mtr

trx_sysf_rseg_get_space()

static space_id_t trx_sysf_rseg_get_space ( trx_sysf_t *  sys_header, ulint  slot, mtr_t *  mtr  )

inlinestatic

Gets the space of the nth rollback segment slot in the trx system file copy.

Returns

space id

Parameters

sys_header	in: trx sys header
slot	in: slot index == rseg id
mtr	in: mtr

trx_sysf_rseg_set_page_no()

static void trx_sysf_rseg_set_page_no ( trx_sysf_t *  sys_header, ulint  slot, page_no_t  page_no, mtr_t *  mtr  )

inlinestatic

Sets the page number of the nth rollback segment slot in the trx system header.

Parameters

sys_header	in: trx sys header
slot	in: slot index == rseg id
page_no	in: page number, FIL_NULL if the slot is reset to unused
mtr	in: mtr

trx_sysf_rseg_set_space()

static void trx_sysf_rseg_set_space ( trx_sysf_t *  sys_header, ulint  slot, space_id_t  space, mtr_t *  mtr  )

inlinestatic

Sets the space id of the nth rollback segment slot in the trx system file copy.

Parameters

sys_header	in: trx sys file copy
slot	in: slot index == rseg id
space	in: space id
mtr	in: mtr

trx_write_trx_id()

static void trx_write_trx_id ( byte *  ptr, trx_id_t  id  )

inlinestatic

Writes a trx id to an index page.

In case that the id size changes in some future version, this function should be used instead of mach_write_...

Parameters

ptr	in: pointer to memory where written
id	in: id

Variable Documentation

TRX_SYS_RSEG_PAGE_NO

constexpr uint32_t TRX_SYS_RSEG_PAGE_NO = 4

constexpr

page number where the segment header is placed; this is FIL_NULL if the slot is unused

TRX_SYS_RSEG_SLOT_SIZE

constexpr uint32_t TRX_SYS_RSEG_SLOT_SIZE = 8

constexpr

TRX_SYS_RSEG_SPACE

constexpr uint32_t TRX_SYS_RSEG_SPACE = 0

constexpr

space where the segment header is placed; starting with MySQL/InnoDB 5.1.7, this is UNIV_UNDEFINED if the slot is unused