trx0rseg.ic File Reference

Rollback segment. More...

#include "mtr0log.h"
#include "srv0srv.h"
#include "trx0purge.h"
#include "trx0sys.h"

Functions
static trx_rsegf_t *	trx_rsegf_get (space_id_t space, page_no_t page_no, const page_size_t &page_size, mtr_t *mtr)
	Gets a rollback segment header. More...
static trx_rsegf_t *	trx_rsegf_get_new (space_id_t space, page_no_t page_no, const page_size_t &page_size, mtr_t *mtr)
	Gets a newly created rollback segment header. More...
static page_no_t	trx_rsegf_get_nth_undo (trx_rsegf_t *rsegf, ulint n, mtr_t *mtr)
	Gets the file page number of the nth undo log slot. More...
static void	trx_rsegf_set_nth_undo (trx_rsegf_t *rsegf, ulint n, page_no_t page_no, mtr_t *mtr)
	Sets the file page number of the nth undo log slot. More...
static ulint	trx_rsegf_undo_find_free (trx_rsegf_t *rsegf, mtr_t *mtr)
	Looks for a free slot for an undo log segment. More...
space_id_t	trx_rseg_id_to_space_id (ulint id, bool is_temp)
	Convert a 7-bit ID stored in a rollback pointer to an undo space ID. More...
trx_rsegsf_t *	trx_rsegsf_get (space_id_t space_id, mtr_t *mtr)
	Get a pointer to the rollback segment directory header and x-latches its page. More...
page_no_t	trx_rsegsf_get_page_no (trx_rsegsf_t *rsegs_header, ulint slot, mtr_t *mtr)
	Get the page number of the nth rollback segment slot in the RSEG_ARRAY page for this undo tablespace. More...
static void	trx_rsegsf_set_page_no (trx_rsegsf_t *rsegs_header, ulint slot, page_no_t page_no, mtr_t *mtr)
	Sets the page number of the nth rollback segment slot in the independent undo tablespace. More...

Detailed Description

Rollback segment.

Created 3/26/1996 Heikki Tuuri

Function Documentation

trx_rseg_id_to_space_id()

space_id_t trx_rseg_id_to_space_id ( ulint  id, bool  is_temp  )

inline

Convert a 7-bit ID stored in a rollback pointer to an undo space ID.

Before 8.0, this ID is called an rseg_id and is a slot in the TRX_SYS page where the space_id can be read. After 8.0 this is an undo space number which can be converted directly to an undo space ID.

Parameters

[in]	id	a 7-bit ID from a rollback pointer
[in]	is_temp	true if rseg from Temp Tablespace else false.

Returns

undo tablespace ID containing the rollback segment

trx_rsegf_get()

static trx_rsegf_t * trx_rsegf_get ( space_id_t  space, page_no_t  page_no, const page_size_t &  page_size, mtr_t *  mtr  )

inlinestatic

Gets a rollback segment header.

Parameters

[in]	space	Space where placed
[in]	page_no	Page number of the header
[in]	page_size	Page size
[in,out]	mtr	Mini-transaction

Returns

rollback segment header, page x-latched

trx_rsegf_get_new()

static trx_rsegf_t * trx_rsegf_get_new ( space_id_t  space, page_no_t  page_no, const page_size_t &  page_size, mtr_t *  mtr  )

inlinestatic

Gets a newly created rollback segment header.

Parameters

[in]	space	Space where placed
[in]	page_no	Page number of the header
[in]	page_size	Page size
[in,out]	mtr	Mini-transaction

Returns

rollback segment header, page x-latched

trx_rsegf_get_nth_undo()

static page_no_t trx_rsegf_get_nth_undo ( trx_rsegf_t *  rsegf, ulint  n, mtr_t *  mtr  )

inlinestatic

Gets the file page number of the nth undo log slot.

Returns

page number of the undo log segment

Parameters

rsegf	in: rollback segment header
n	in: index of slot
mtr	in: mtr

trx_rsegf_set_nth_undo()

static void trx_rsegf_set_nth_undo ( trx_rsegf_t *  rsegf, ulint  n, page_no_t  page_no, mtr_t *  mtr  )

inlinestatic

Sets the file page number of the nth undo log slot.

Parameters

rsegf	in: rollback segment header
n	in: index of slot
page_no	in: page number of the undo log segment
mtr	in: mtr

trx_rsegf_undo_find_free()

static ulint trx_rsegf_undo_find_free ( trx_rsegf_t *  rsegf, mtr_t *  mtr  )

inlinestatic

Looks for a free slot for an undo log segment.

Returns

slot index or ULINT_UNDEFINED if not found

Parameters

rsegf	in: rollback segment header
mtr	in: mtr

trx_rsegsf_get()

trx_rsegsf_t * trx_rsegsf_get ( space_id_t  space_id, mtr_t *  mtr  )

inline

Get a pointer to the rollback segment directory header and x-latches its page.

Parameters

[in]	space_id	Undo Tablespace ID
[in]	mtr	mtr

Returns

pointer to rollback segment directory header with page x-latched.

trx_rsegsf_get_page_no()

page_no_t trx_rsegsf_get_page_no ( trx_rsegsf_t *  rsegs_header, ulint  slot, mtr_t *  mtr  )

inline

Get the page number of the nth rollback segment slot in the RSEG_ARRAY page for this undo tablespace.

Parameters

[in]	rsegs_header	rollback segment array page header
[in]	slot	slot index == rseg id
[in]	mtr	mtr

Returns

page number, FIL_NULL if slot unused

trx_rsegsf_set_page_no()

static void trx_rsegsf_set_page_no ( trx_rsegsf_t *  rsegs_header, ulint  slot, page_no_t  page_no, mtr_t *  mtr  )

inlinestatic

Sets the page number of the nth rollback segment slot in the independent undo tablespace.

Parameters

[in]	rsegs_header	rollback segment array page header
[in]	slot	slot number on page == rseg id
[in]	page_no	rollback regment header page number
[in]	mtr	mtr