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63574f1275
The InnoDB source code contains quite a few references to a closed-source hot backup tool which was originally called InnoDB Hot Backup (ibbackup) and later incorporated in MySQL Enterprise Backup. The open source backup tool XtraBackup uses the full database for recovery. So, the references to UNIV_HOTBACKUP are only cluttering the source code.
668 lines
24 KiB
C++
668 lines
24 KiB
C++
/*****************************************************************************
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Copyright (c) 1996, 2016, Oracle and/or its affiliates. All Rights Reserved.
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This program is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free Software
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Foundation; version 2 of the License.
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This program is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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You should have received a copy of the GNU General Public License along with
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this program; if not, write to the Free Software Foundation, Inc.,
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51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
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*****************************************************************************/
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/**************************************************//**
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@file include/trx0sys.h
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Transaction system
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Created 3/26/1996 Heikki Tuuri
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*******************************************************/
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#ifndef trx0sys_h
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#define trx0sys_h
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#include "univ.i"
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#include "buf0buf.h"
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#include "fil0fil.h"
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#include "trx0types.h"
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#include "mem0mem.h"
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#include "mtr0mtr.h"
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#include "ut0byte.h"
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#include "mem0mem.h"
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#include "ut0lst.h"
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#include "read0types.h"
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#include "page0types.h"
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#include "ut0mutex.h"
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#include "trx0trx.h"
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#ifdef WITH_WSREP
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#include "trx0xa.h"
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#endif /* WITH_WSREP */
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typedef UT_LIST_BASE_NODE_T(trx_t) trx_ut_list_t;
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// Forward declaration
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class MVCC;
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class ReadView;
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/** The transaction system */
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extern trx_sys_t* trx_sys;
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/** Checks if a page address is the trx sys header page.
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@param[in] page_id page id
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@return true if trx sys header page */
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UNIV_INLINE
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bool
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trx_sys_hdr_page(
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const page_id_t& page_id);
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/*****************************************************************//**
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Creates and initializes the central memory structures for the transaction
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system. This is called when the database is started.
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@return min binary heap of rsegs to purge */
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purge_pq_t*
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trx_sys_init_at_db_start(void);
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/*==========================*/
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/*****************************************************************//**
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Creates the trx_sys instance and initializes purge_queue and mutex. */
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void
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trx_sys_create(void);
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/*================*/
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/*****************************************************************//**
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Creates and initializes the transaction system at the database creation. */
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void
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trx_sys_create_sys_pages(void);
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/*==========================*/
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/****************************************************************//**
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Looks for a free slot for a rollback segment in the trx system file copy.
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@return slot index or ULINT_UNDEFINED if not found */
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ulint
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trx_sysf_rseg_find_free(
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/*====================*/
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mtr_t* mtr, /*!< in/out: mtr */
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bool include_tmp_slots, /*!< in: if true, report slots reserved
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for temp-tablespace as free slots. */
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ulint nth_free_slots); /*!< in: allocate nth free slot.
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0 means next free slot. */
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/***************************************************************//**
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Gets the pointer in the nth slot of the rseg array.
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@return pointer to rseg object, NULL if slot not in use */
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UNIV_INLINE
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trx_rseg_t*
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trx_sys_get_nth_rseg(
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/*=================*/
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trx_sys_t* sys, /*!< in: trx system */
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ulint n, /*!< in: index of slot */
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bool is_redo_rseg); /*!< in: true if redo rseg. */
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/**********************************************************************//**
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Gets a pointer to the transaction system file copy and x-locks its page.
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@return pointer to system file copy, page x-locked */
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UNIV_INLINE
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trx_sysf_t*
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trx_sysf_get(
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/*=========*/
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mtr_t* mtr); /*!< in: mtr */
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/*****************************************************************//**
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Gets the space of the nth rollback segment slot in the trx system
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file copy.
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@return space id */
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UNIV_INLINE
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ulint
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trx_sysf_rseg_get_space(
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/*====================*/
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trx_sysf_t* sys_header, /*!< in: trx sys file copy */
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ulint i, /*!< in: slot index == rseg id */
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mtr_t* mtr); /*!< in: mtr */
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/*****************************************************************//**
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Gets the page number of the nth rollback segment slot in the trx system
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file copy.
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@return page number, FIL_NULL if slot unused */
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UNIV_INLINE
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ulint
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trx_sysf_rseg_get_page_no(
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/*======================*/
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trx_sysf_t* sys_header, /*!< in: trx sys file copy */
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ulint i, /*!< in: slot index == rseg id */
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mtr_t* mtr); /*!< in: mtr */
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/*****************************************************************//**
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Sets the space id of the nth rollback segment slot in the trx system
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file copy. */
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UNIV_INLINE
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void
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trx_sysf_rseg_set_space(
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/*====================*/
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trx_sysf_t* sys_header, /*!< in: trx sys file copy */
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ulint i, /*!< in: slot index == rseg id */
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ulint space, /*!< in: space id */
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mtr_t* mtr); /*!< in: mtr */
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/*****************************************************************//**
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Sets the page number of the nth rollback segment slot in the trx system
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file copy. */
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UNIV_INLINE
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void
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trx_sysf_rseg_set_page_no(
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/*======================*/
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trx_sysf_t* sys_header, /*!< in: trx sys file copy */
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ulint i, /*!< in: slot index == rseg id */
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ulint page_no, /*!< in: page number, FIL_NULL if
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the slot is reset to unused */
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mtr_t* mtr); /*!< in: mtr */
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/*****************************************************************//**
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Allocates a new transaction id.
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@return new, allocated trx id */
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UNIV_INLINE
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trx_id_t
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trx_sys_get_new_trx_id();
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/*===================*/
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/*****************************************************************//**
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Determines the maximum transaction id.
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@return maximum currently allocated trx id; will be stale after the
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next call to trx_sys_get_new_trx_id() */
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UNIV_INLINE
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trx_id_t
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trx_sys_get_max_trx_id(void);
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/*========================*/
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#ifdef UNIV_DEBUG
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/* Flag to control TRX_RSEG_N_SLOTS behavior debugging. */
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extern uint trx_rseg_n_slots_debug;
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#endif
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/*****************************************************************//**
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Check if slot-id is reserved slot-id for noredo rsegs. */
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UNIV_INLINE
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bool
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trx_sys_is_noredo_rseg_slot(
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/*========================*/
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ulint slot_id); /*!< in: slot_id to check */
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/*****************************************************************//**
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Writes a trx id to an index page. In case that the id size changes in
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some future version, this function should be used instead of
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mach_write_... */
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UNIV_INLINE
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void
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trx_write_trx_id(
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/*=============*/
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byte* ptr, /*!< in: pointer to memory where written */
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trx_id_t id); /*!< in: id */
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/*****************************************************************//**
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Reads a trx id from an index page. In case that the id size changes in
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some future version, this function should be used instead of
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mach_read_...
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@return id */
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UNIV_INLINE
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trx_id_t
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trx_read_trx_id(
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/*============*/
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const byte* ptr); /*!< in: pointer to memory from where to read */
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/****************************************************************//**
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Looks for the trx instance with the given id in the rw trx_list.
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@return the trx handle or NULL if not found */
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UNIV_INLINE
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trx_t*
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trx_get_rw_trx_by_id(
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/*=================*/
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trx_id_t trx_id);/*!< in: trx id to search for */
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/****************************************************************//**
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Returns the minimum trx id in rw trx list. This is the smallest id for which
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the trx can possibly be active. (But, you must look at the trx->state to
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find out if the minimum trx id transaction itself is active, or already
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committed.)
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@return the minimum trx id, or trx_sys->max_trx_id if the trx list is empty */
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UNIV_INLINE
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trx_id_t
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trx_rw_min_trx_id(void);
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/*===================*/
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/****************************************************************//**
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Checks if a rw transaction with the given id is active.
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@return transaction instance if active, or NULL */
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UNIV_INLINE
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trx_t*
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trx_rw_is_active_low(
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/*=================*/
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trx_id_t trx_id, /*!< in: trx id of the transaction */
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ibool* corrupt); /*!< in: NULL or pointer to a flag
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that will be set if corrupt */
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/****************************************************************//**
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Checks if a rw transaction with the given id is active. If the caller is
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not holding trx_sys->mutex, the transaction may already have been
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committed.
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@return transaction instance if active, or NULL; */
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UNIV_INLINE
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trx_t*
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trx_rw_is_active(
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/*=============*/
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trx_id_t trx_id, /*!< in: trx id of the transaction */
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ibool* corrupt, /*!< in: NULL or pointer to a flag
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that will be set if corrupt */
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bool do_ref_count); /*!< in: if true then increment the
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trx_t::n_ref_count */
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#ifdef UNIV_DEBUG
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/****************************************************************//**
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Checks whether a trx is in on of rw_trx_list
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@return TRUE if is in */
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bool
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trx_in_rw_trx_list(
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/*============*/
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const trx_t* in_trx) /*!< in: transaction */
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MY_ATTRIBUTE((warn_unused_result));
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#endif /* UNIV_DEBUG */
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#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
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/***********************************************************//**
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Assert that a transaction has been recovered.
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@return TRUE */
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UNIV_INLINE
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ibool
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trx_assert_recovered(
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/*=================*/
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trx_id_t trx_id) /*!< in: transaction identifier */
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MY_ATTRIBUTE((warn_unused_result));
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#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
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/*****************************************************************//**
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Updates the offset information about the end of the MySQL binlog entry
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which corresponds to the transaction just being committed. In a MySQL
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replication slave updates the latest master binlog position up to which
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replication has proceeded. */
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void
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trx_sys_update_mysql_binlog_offset(
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/*===============================*/
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const char* file_name,/*!< in: MySQL log file name */
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int64_t offset, /*!< in: position in that log file */
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ulint field, /*!< in: offset of the MySQL log info field in
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the trx sys header */
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trx_sysf_t* sys_header, /*!< in: trx sys header */
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mtr_t* mtr); /*!< in: mtr */
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/*****************************************************************//**
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Prints to stderr the MySQL binlog offset info in the trx system header if
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the magic number shows it valid. */
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void
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trx_sys_print_mysql_binlog_offset(void);
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/*===================================*/
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#ifdef WITH_WSREP
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/** Update WSREP checkpoint XID in sys header. */
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void
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trx_sys_update_wsrep_checkpoint(
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/*============================*/
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const XID* xid, /*!< in: WSREP XID */
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trx_sysf_t* sys_header, /*!< in: sys_header */
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mtr_t* mtr); /*!< in: mtr */
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void
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/** Read WSREP checkpoint XID from sys header. */
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trx_sys_read_wsrep_checkpoint(
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/*==========================*/
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XID* xid); /*!< out: WSREP XID */
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#endif /* WITH_WSREP */
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/** Initializes the tablespace tag system. */
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void
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trx_sys_file_format_init(void);
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/*==========================*/
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/*****************************************************************//**
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Closes the tablespace tag system. */
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void
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trx_sys_file_format_close(void);
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/*===========================*/
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/********************************************************************//**
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Tags the system table space with minimum format id if it has not been
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tagged yet.
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WARNING: This function is only called during the startup and AFTER the
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redo log application during recovery has finished. */
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void
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trx_sys_file_format_tag_init(void);
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/*==============================*/
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/*****************************************************************//**
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Shutdown/Close the transaction system. */
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void
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trx_sys_close(void);
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/*===============*/
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/*****************************************************************//**
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Get the name representation of the file format from its id.
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@return pointer to the name */
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const char*
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trx_sys_file_format_id_to_name(
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/*===========================*/
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const ulint id); /*!< in: id of the file format */
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/*****************************************************************//**
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Set the file format id unconditionally except if it's already the
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same value.
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@return TRUE if value updated */
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ibool
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trx_sys_file_format_max_set(
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/*========================*/
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ulint format_id, /*!< in: file format id */
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const char** name); /*!< out: max file format name or
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NULL if not needed. */
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/*********************************************************************
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Creates the rollback segments
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@return number of rollback segments that are active. */
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ulint
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trx_sys_create_rsegs(
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/*=================*/
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ulint n_spaces, /*!< number of tablespaces for UNDO logs */
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ulint n_rsegs, /*!< number of rollback segments to create */
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ulint n_tmp_rsegs); /*!< number of rollback segments reserved for
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temp-tables. */
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/*****************************************************************//**
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Get the number of transaction in the system, independent of their state.
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@return count of transactions in trx_sys_t::trx_list */
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UNIV_INLINE
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ulint
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trx_sys_get_n_rw_trx(void);
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/*======================*/
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/*********************************************************************
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Check if there are any active (non-prepared) transactions.
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@return total number of active transactions or 0 if none */
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ulint
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trx_sys_any_active_transactions(void);
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/*=================================*/
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/*****************************************************************//**
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Get the name representation of the file format from its id.
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@return pointer to the max format name */
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const char*
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trx_sys_file_format_max_get(void);
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/*=============================*/
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/*****************************************************************//**
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Check for the max file format tag stored on disk.
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@return DB_SUCCESS or error code */
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dberr_t
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trx_sys_file_format_max_check(
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/*==========================*/
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ulint max_format_id); /*!< in: the max format id to check */
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/********************************************************************//**
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Update the file format tag in the system tablespace only if the given
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format id is greater than the known max id.
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@return TRUE if format_id was bigger than the known max id */
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ibool
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trx_sys_file_format_max_upgrade(
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/*============================*/
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const char** name, /*!< out: max file format name */
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ulint format_id); /*!< in: file format identifier */
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/*****************************************************************//**
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Get the name representation of the file format from its id.
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@return pointer to the name */
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const char*
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trx_sys_file_format_id_to_name(
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/*===========================*/
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const ulint id); /*!< in: id of the file format */
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/**
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Add the transaction to the RW transaction set
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@param trx transaction instance to add */
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UNIV_INLINE
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void
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trx_sys_rw_trx_add(trx_t* trx);
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#ifdef UNIV_DEBUG
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/*************************************************************//**
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Validate the trx_sys_t::rw_trx_list.
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@return true if the list is valid */
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bool
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trx_sys_validate_trx_list();
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/*========================*/
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#endif /* UNIV_DEBUG */
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/** The automatically created system rollback segment has this id */
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#define TRX_SYS_SYSTEM_RSEG_ID 0
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/** The offset of the transaction system header on the page */
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#define TRX_SYS FSEG_PAGE_DATA
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/** Transaction system header */
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/*------------------------------------------------------------- @{ */
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#define TRX_SYS_TRX_ID_STORE 0 /*!< the maximum trx id or trx
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number modulo
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TRX_SYS_TRX_ID_UPDATE_MARGIN
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written to a file page by any
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transaction; the assignment of
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transaction ids continues from
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this number rounded up by
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TRX_SYS_TRX_ID_UPDATE_MARGIN
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plus
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TRX_SYS_TRX_ID_UPDATE_MARGIN
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when the database is
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started */
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#define TRX_SYS_FSEG_HEADER 8 /*!< segment header for the
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tablespace segment the trx
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system is created into */
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#define TRX_SYS_RSEGS (8 + FSEG_HEADER_SIZE)
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/*!< the start of the array of
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rollback segment specification
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slots */
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/*------------------------------------------------------------- @} */
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/* Max number of rollback segments: the number of segment specification slots
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in the transaction system array; rollback segment id must fit in one (signed)
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byte, therefore 128; each slot is currently 8 bytes in size. If you want
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to raise the level to 256 then you will need to fix some assertions that
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impose the 7 bit restriction. e.g., mach_write_to_3() */
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#define TRX_SYS_N_RSEGS 128
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/* Originally, InnoDB defined TRX_SYS_N_RSEGS as 256 but created only one
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rollback segment. It initialized some arrays with this number of entries.
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We must remember this limit in order to keep file compatibility. */
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#define TRX_SYS_OLD_N_RSEGS 256
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/** Maximum length of MySQL binlog file name, in bytes. */
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#define TRX_SYS_MYSQL_LOG_NAME_LEN 512
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/** Contents of TRX_SYS_MYSQL_LOG_MAGIC_N_FLD */
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#define TRX_SYS_MYSQL_LOG_MAGIC_N 873422344
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#if UNIV_PAGE_SIZE_MIN < 4096
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# error "UNIV_PAGE_SIZE_MIN < 4096"
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#endif
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/** The offset of the MySQL binlog offset info in the trx system header */
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#define TRX_SYS_MYSQL_LOG_INFO (UNIV_PAGE_SIZE - 1000)
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#define TRX_SYS_MYSQL_LOG_MAGIC_N_FLD 0 /*!< magic number which is
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TRX_SYS_MYSQL_LOG_MAGIC_N
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if we have valid data in the
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MySQL binlog info */
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#define TRX_SYS_MYSQL_LOG_OFFSET_HIGH 4 /*!< high 4 bytes of the offset
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within that file */
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#define TRX_SYS_MYSQL_LOG_OFFSET_LOW 8 /*!< low 4 bytes of the offset
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within that file */
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#define TRX_SYS_MYSQL_LOG_NAME 12 /*!< MySQL log file name */
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#ifdef WITH_WSREP
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/* The offset to WSREP XID headers */
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#define TRX_SYS_WSREP_XID_INFO (UNIV_PAGE_SIZE - 3500)
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#define TRX_SYS_WSREP_XID_MAGIC_N_FLD 0
|
|
#define TRX_SYS_WSREP_XID_MAGIC_N 0x77737265
|
|
|
|
/* XID field: formatID, gtrid_len, bqual_len, xid_data */
|
|
#define TRX_SYS_WSREP_XID_LEN (4 + 4 + 4 + XIDDATASIZE)
|
|
#define TRX_SYS_WSREP_XID_FORMAT 4
|
|
#define TRX_SYS_WSREP_XID_GTRID_LEN 8
|
|
#define TRX_SYS_WSREP_XID_BQUAL_LEN 12
|
|
#define TRX_SYS_WSREP_XID_DATA 16
|
|
#endif /* WITH_WSREP*/
|
|
|
|
/** Doublewrite buffer */
|
|
/* @{ */
|
|
/** The offset of the doublewrite buffer header on the trx system header page */
|
|
#define TRX_SYS_DOUBLEWRITE (UNIV_PAGE_SIZE - 200)
|
|
/*-------------------------------------------------------------*/
|
|
#define TRX_SYS_DOUBLEWRITE_FSEG 0 /*!< fseg header of the fseg
|
|
containing the doublewrite
|
|
buffer */
|
|
#define TRX_SYS_DOUBLEWRITE_MAGIC FSEG_HEADER_SIZE
|
|
/*!< 4-byte magic number which
|
|
shows if we already have
|
|
created the doublewrite
|
|
buffer */
|
|
#define TRX_SYS_DOUBLEWRITE_BLOCK1 (4 + FSEG_HEADER_SIZE)
|
|
/*!< page number of the
|
|
first page in the first
|
|
sequence of 64
|
|
(= FSP_EXTENT_SIZE) consecutive
|
|
pages in the doublewrite
|
|
buffer */
|
|
#define TRX_SYS_DOUBLEWRITE_BLOCK2 (8 + FSEG_HEADER_SIZE)
|
|
/*!< page number of the
|
|
first page in the second
|
|
sequence of 64 consecutive
|
|
pages in the doublewrite
|
|
buffer */
|
|
#define TRX_SYS_DOUBLEWRITE_REPEAT 12 /*!< we repeat
|
|
TRX_SYS_DOUBLEWRITE_MAGIC,
|
|
TRX_SYS_DOUBLEWRITE_BLOCK1,
|
|
TRX_SYS_DOUBLEWRITE_BLOCK2
|
|
so that if the trx sys
|
|
header is half-written
|
|
to disk, we still may
|
|
be able to recover the
|
|
information */
|
|
/** If this is not yet set to TRX_SYS_DOUBLEWRITE_SPACE_ID_STORED_N,
|
|
we must reset the doublewrite buffer, because starting from 4.1.x the
|
|
space id of a data page is stored into
|
|
FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID. */
|
|
#define TRX_SYS_DOUBLEWRITE_SPACE_ID_STORED (24 + FSEG_HEADER_SIZE)
|
|
|
|
/*-------------------------------------------------------------*/
|
|
/** Contents of TRX_SYS_DOUBLEWRITE_MAGIC */
|
|
#define TRX_SYS_DOUBLEWRITE_MAGIC_N 536853855
|
|
/** Contents of TRX_SYS_DOUBLEWRITE_SPACE_ID_STORED */
|
|
#define TRX_SYS_DOUBLEWRITE_SPACE_ID_STORED_N 1783657386
|
|
|
|
/** Size of the doublewrite block in pages */
|
|
#define TRX_SYS_DOUBLEWRITE_BLOCK_SIZE FSP_EXTENT_SIZE
|
|
/* @} */
|
|
|
|
/** File format tag */
|
|
/* @{ */
|
|
/** The offset of the file format tag on the trx system header page
|
|
(TRX_SYS_PAGE_NO of TRX_SYS_SPACE) */
|
|
#define TRX_SYS_FILE_FORMAT_TAG (UNIV_PAGE_SIZE - 16)
|
|
|
|
/** Contents of TRX_SYS_FILE_FORMAT_TAG when valid. The file format
|
|
identifier is added to this constant. */
|
|
#define TRX_SYS_FILE_FORMAT_TAG_MAGIC_N_LOW 3645922177UL
|
|
/** Contents of TRX_SYS_FILE_FORMAT_TAG+4 when valid */
|
|
#define TRX_SYS_FILE_FORMAT_TAG_MAGIC_N_HIGH 2745987765UL
|
|
/** Contents of TRX_SYS_FILE_FORMAT_TAG when valid. The file format
|
|
identifier is added to this 64-bit constant. */
|
|
#define TRX_SYS_FILE_FORMAT_TAG_MAGIC_N \
|
|
((ib_uint64_t) TRX_SYS_FILE_FORMAT_TAG_MAGIC_N_HIGH << 32 \
|
|
| TRX_SYS_FILE_FORMAT_TAG_MAGIC_N_LOW)
|
|
/* @} */
|
|
|
|
/** The transaction system central memory data structure. */
|
|
struct trx_sys_t {
|
|
|
|
TrxSysMutex mutex; /*!< mutex protecting most fields in
|
|
this structure except when noted
|
|
otherwise */
|
|
|
|
MVCC* mvcc; /*!< Multi version concurrency control
|
|
manager */
|
|
volatile trx_id_t
|
|
max_trx_id; /*!< The smallest number not yet
|
|
assigned as a transaction id or
|
|
transaction number. This is declared
|
|
volatile because it can be accessed
|
|
without holding any mutex during
|
|
AC-NL-RO view creation. */
|
|
trx_ut_list_t serialisation_list;
|
|
/*!< Ordered on trx_t::no of all the
|
|
currenrtly active RW transactions */
|
|
#ifdef UNIV_DEBUG
|
|
trx_id_t rw_max_trx_id; /*!< Max trx id of read-write
|
|
transactions which exist or existed */
|
|
#endif /* UNIV_DEBUG */
|
|
|
|
char pad1[64]; /*!< To avoid false sharing */
|
|
trx_ut_list_t rw_trx_list; /*!< List of active and committed in
|
|
memory read-write transactions, sorted
|
|
on trx id, biggest first. Recovered
|
|
transactions are always on this list. */
|
|
|
|
char pad2[64]; /*!< To avoid false sharing */
|
|
trx_ut_list_t mysql_trx_list; /*!< List of transactions created
|
|
for MySQL. All user transactions are
|
|
on mysql_trx_list. The rw_trx_list
|
|
can contain system transactions and
|
|
recovered transactions that will not
|
|
be in the mysql_trx_list.
|
|
mysql_trx_list may additionally contain
|
|
transactions that have not yet been
|
|
started in InnoDB. */
|
|
|
|
trx_ids_t rw_trx_ids; /*!< Array of Read write transaction IDs
|
|
for MVCC snapshot. A ReadView would take
|
|
a snapshot of these transactions whose
|
|
changes are not visible to it. We should
|
|
remove transactions from the list before
|
|
committing in memory and releasing locks
|
|
to ensure right order of removal and
|
|
consistent snapshot. */
|
|
|
|
char pad3[64]; /*!< To avoid false sharing */
|
|
trx_rseg_t* rseg_array[TRX_SYS_N_RSEGS];
|
|
/*!< Pointer array to rollback
|
|
segments; NULL if slot not in use;
|
|
created and destroyed in
|
|
single-threaded mode; not protected
|
|
by any mutex, because it is read-only
|
|
during multi-threaded operation */
|
|
ulint rseg_history_len;
|
|
/*!< Length of the TRX_RSEG_HISTORY
|
|
list (update undo logs for committed
|
|
transactions), protected by
|
|
rseg->mutex */
|
|
|
|
trx_rseg_t* const pending_purge_rseg_array[TRX_SYS_N_RSEGS];
|
|
/*!< Pointer array to rollback segments
|
|
between slot-1..slot-srv_tmp_undo_logs
|
|
that are now replaced by non-redo
|
|
rollback segments. We need them for
|
|
scheduling purge if any of the rollback
|
|
segment has pending records to purge. */
|
|
|
|
TrxIdSet rw_trx_set; /*!< Mapping from transaction id
|
|
to transaction instance */
|
|
|
|
ulint n_prepared_trx; /*!< Number of transactions currently
|
|
in the XA PREPARED state */
|
|
|
|
ulint n_prepared_recovered_trx; /*!< Number of transactions
|
|
currently in XA PREPARED state that are
|
|
also recovered. Such transactions cannot
|
|
be added during runtime. They can only
|
|
occur after recovery if mysqld crashed
|
|
while there were XA PREPARED
|
|
transactions. We disable query cache
|
|
if such transactions exist. */
|
|
};
|
|
|
|
/** When a trx id which is zero modulo this number (which must be a power of
|
|
two) is assigned, the field TRX_SYS_TRX_ID_STORE on the transaction system
|
|
page is updated */
|
|
#define TRX_SYS_TRX_ID_WRITE_MARGIN ((trx_id_t) 256)
|
|
|
|
/** Test if trx_sys->mutex is owned. */
|
|
#define trx_sys_mutex_own() (trx_sys->mutex.is_owned())
|
|
|
|
/** Acquire the trx_sys->mutex. */
|
|
#define trx_sys_mutex_enter() do { \
|
|
mutex_enter(&trx_sys->mutex); \
|
|
} while (0)
|
|
|
|
/** Release the trx_sys->mutex. */
|
|
#define trx_sys_mutex_exit() do { \
|
|
trx_sys->mutex.exit(); \
|
|
} while (0)
|
|
|
|
#ifndef UNIV_NONINL
|
|
#include "trx0sys.ic"
|
|
#endif
|
|
|
|
#endif
|