#include "univ.i"#include "trx0types.h"#include "fsp0types.h"#include "fil0fil.h"#include "buf0buf.h"#include "mtr0mtr.h"#include "ut0byte.h"#include "mem0mem.h"#include "sync0sync.h"#include "ut0lst.h"#include "ut0bh.h"#include "read0types.h"#include "page0types.h"#include "fsp0fsp.h"#include "trx0sys.ic"
Go to the source code of this file.
Data Structures | |
| struct | trx_sys_t |
Typedefs | |
| typedef ut_list_base< trx_t > | trx_list_t |
Functions | |
| UNIV_INLINE ibool | trx_sys_hdr_page (ulint space, ulint page_no) |
| UNIV_INTERN ib_bh_t * | trx_sys_init_at_db_start (void) |
| UNIV_INTERN void | trx_sys_create (void) |
| UNIV_INTERN void | trx_sys_create_sys_pages (void) |
| UNIV_INTERN ulint | trx_sysf_rseg_find_free (mtr_t *mtr) |
| UNIV_INLINE trx_rseg_t * | trx_sys_get_nth_rseg (trx_sys_t *sys, ulint n) |
| UNIV_INLINE trx_sysf_t * | trx_sysf_get (mtr_t *mtr) |
| UNIV_INLINE ulint | trx_sysf_rseg_get_space (trx_sysf_t *sys_header, ulint i, mtr_t *mtr) |
| UNIV_INLINE ulint | trx_sysf_rseg_get_page_no (trx_sysf_t *sys_header, ulint i, mtr_t *mtr) |
| UNIV_INLINE void | trx_sysf_rseg_set_space (trx_sysf_t *sys_header, ulint i, ulint space, mtr_t *mtr) |
| UNIV_INLINE void | trx_sysf_rseg_set_page_no (trx_sysf_t *sys_header, ulint i, ulint page_no, mtr_t *mtr) |
| UNIV_INLINE trx_id_t | trx_sys_get_new_trx_id (void) |
| UNIV_INLINE trx_id_t | trx_sys_get_max_trx_id (void) |
| UNIV_INLINE void | trx_write_trx_id (byte *ptr, trx_id_t id) |
| UNIV_INLINE trx_id_t | trx_read_trx_id (const byte *ptr) |
| UNIV_INLINE trx_t * | trx_get_rw_trx_by_id (trx_id_t trx_id) |
| UNIV_INLINE trx_id_t | trx_rw_min_trx_id (void) |
| UNIV_INLINE trx_t * | trx_rw_is_active_low (trx_id_t trx_id, ibool *corrupt) |
| UNIV_INLINE trx_t * | trx_rw_is_active (trx_id_t trx_id, ibool *corrupt) |
| UNIV_INTERN ibool | trx_in_trx_list (const trx_t *in_trx)) |
| UNIV_INLINE ibool | trx_assert_recovered (trx_id_t trx_id)) |
| UNIV_INTERN void | trx_sys_update_mysql_binlog_offset (const char *file_name, ib_int64_t offset, ulint field, mtr_t *mtr) |
| UNIV_INTERN void | trx_sys_print_mysql_binlog_offset (void) |
| UNIV_INTERN void | trx_sys_print_mysql_master_log_pos (void) |
| UNIV_INTERN void | trx_sys_file_format_init (void) |
| UNIV_INTERN void | trx_sys_file_format_close (void) |
| UNIV_INTERN void | trx_sys_file_format_tag_init (void) |
| UNIV_INTERN void | trx_sys_close (void) |
| UNIV_INTERN const char * | trx_sys_file_format_id_to_name (const ulint id) |
| UNIV_INTERN ibool | trx_sys_file_format_max_set (ulint format_id, const char **name) |
| UNIV_INTERN ulint | trx_sys_create_rsegs (ulint n_spaces, ulint n_rsegs) |
| UNIV_INLINE ulint | trx_sys_get_n_rw_trx (void) |
| UNIV_INTERN ulint | trx_sys_any_active_transactions (void) |
| UNIV_INTERN const char * | trx_sys_file_format_max_get (void) |
| UNIV_INTERN dberr_t | trx_sys_file_format_max_check (ulint max_format_id) |
| UNIV_INTERN ibool | trx_sys_file_format_max_upgrade (const char **name, ulint format_id) |
| UNIV_INTERN ibool | trx_sys_validate_trx_list (void) |
Variables | |
| trx_sys_t * | trx_sys |
| uint | trx_rseg_n_slots_debug |
| char | trx_sys_mysql_master_log_name [] |
| ib_int64_t | trx_sys_mysql_master_log_pos |
| char | trx_sys_mysql_bin_log_name [] |
| ib_int64_t | trx_sys_mysql_bin_log_pos |
Detailed Description
Transaction system
Created 3/26/1996 Heikki Tuuri
Macro Definition Documentation
| #define TRX_SYS_DOUBLEWRITE (UNIV_PAGE_SIZE - 200) |
Doublewrite buffer The offset of the doublewrite buffer header on the trx system header page
| #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_BLOCK_SIZE FSP_EXTENT_SIZE |
Size of the doublewrite block in pages
| #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_MAGIC_N 536853855 |
Contents of TRX_SYS_DOUBLEWRITE_MAGIC
| #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
| #define TRX_SYS_DOUBLEWRITE_SPACE_ID_STORED (24 + FSEG_HEADER_SIZE) |
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_N 1783657386 |
Contents of TRX_SYS_DOUBLEWRITE_SPACE_ID_STORED
| #define TRX_SYS_FILE_FORMAT_TAG (UNIV_PAGE_SIZE - 16) |
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_MAGIC_N |
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_HIGH 2745987765UL |
Contents of TRX_SYS_FILE_FORMAT_TAG+4 when valid
| #define TRX_SYS_FILE_FORMAT_TAG_MAGIC_N_LOW 3645922177UL |
Contents of TRX_SYS_FILE_FORMAT_TAG when valid. The file format
identifier is added to this constant.
| #define TRX_SYS_FSEG_HEADER 8 |
segment header for the tablespace segment the trx system is created into
| #define TRX_SYS_MYSQL_LOG_INFO (UNIV_PAGE_SIZE - 1000) |
The offset of the MySQL binlog offset info in the trx system header
| #define TRX_SYS_MYSQL_LOG_MAGIC_N 873422344 |
Contents of TRX_SYS_MYSQL_LOG_MAGIC_N_FLD
| #define TRX_SYS_MYSQL_LOG_MAGIC_N_FLD 0 |
magic number which is TRX_SYS_MYSQL_LOG_MAGIC_N if we have valid data in the MySQL binlog info
| #define TRX_SYS_MYSQL_LOG_NAME 12 |
MySQL log file name
| #define TRX_SYS_MYSQL_LOG_NAME_LEN 512 |
Maximum length of MySQL binlog file name, in bytes.
| #define TRX_SYS_MYSQL_LOG_OFFSET_HIGH 4 |
high 4 bytes of the offset within that file
| #define TRX_SYS_MYSQL_LOG_OFFSET_LOW 8 |
low 4 bytes of the offset within that file
| #define TRX_SYS_MYSQL_MASTER_LOG_INFO (UNIV_PAGE_SIZE - 2000) |
The offset of the MySQL replication info in the trx system header;
this contains the same fields as TRX_SYS_MYSQL_LOG_INFO below
| #define TRX_SYS_RSEGS (8 + FSEG_HEADER_SIZE) |
the start of the array of rollback segment specification slots
| #define TRX_SYS_TRX_ID_STORE 0 |
Transaction system header the maximum trx id or trx number modulo TRX_SYS_TRX_ID_UPDATE_MARGIN written to a file page by any transaction; the assignment of transaction ids continues from this number rounded up by TRX_SYS_TRX_ID_UPDATE_MARGIN plus TRX_SYS_TRX_ID_UPDATE_MARGIN when the database is started
| #define TRX_SYS_TRX_ID_WRITE_MARGIN 256 |
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
Function Documentation
Assert that a transaction has been recovered.
- Returns
- TRUE
- Parameters
-
trx_id in: transaction identifier
Looks for the trx instance with the given id in the rw trx_list. The caller must be holding trx_sys->mutex.
- Returns
- the trx handle or NULL if not found; the pointer must not be dereferenced unless lock_sys->mutex was acquired before calling this function and is still being held in: trx id to search for
Looks for the trx handle with the given id in rw_trx_list. The caller must be holding trx_sys->mutex.
- Returns
- the trx handle or NULL if not found; the pointer must not be dereferenced unless lock_sys->mutex was acquired before calling this function and is still being held
- Parameters
-
trx_id in: trx id to search for
Checks whether a trx is in one of rw_trx_list or ro_trx_list.
- Returns
- TRUE if is in
- Parameters
-
in_trx in: transaction
| UNIV_INLINE trx_id_t trx_read_trx_id | ( | const byte * | ptr | ) |
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 in: pointer to memory from where to read
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
Checks if a rw transaction with the given id is active. If the caller is not holding lock_sys->mutex, the transaction may already have been committed.
- Returns
- transaction instance if active, or NULL; the pointer must not be dereferenced unless lock_sys->mutex was acquired before calling this function and is still being held in: NULL or pointer to a flag that will be set if corrupt
Checks if a rw transaction with the given id is active. If the caller is not holding lock_sys->mutex, the transaction may already have been committed.
- Returns
- transaction instance if active, or NULL; the pointer must not be dereferenced unless lock_sys->mutex was acquired before calling this function and is still being held
- Parameters
-
trx_id in: trx id of the transaction corrupt in: NULL or pointer to a flag that will be set if corrupt
Checks if a rw transaction with the given id is active. Caller must hold trx_sys->mutex in shared mode. If the caller is not holding lock_sys->mutex, the transaction may already have been committed.
- Returns
- transaction instance if active, or NULL; the pointer must not be dereferenced unless lock_sys->mutex was acquired before calling this function and is still being held in: NULL or pointer to a flag that will be set if corrupt
Checks if a rw transaction with the given id is active. Caller must hold trx_sys->mutex. If the caller is not holding lock_sys->mutex, the transaction may already have been committed.
- Returns
- transaction instance if active, or NULL; the pointer must not be dereferenced unless lock_sys->mutex was acquired before calling this function and is still being held
- Parameters
-
trx_id in: trx id of the transaction corrupt in: NULL or pointer to a flag that will be set if corrupt
| UNIV_INLINE trx_id_t trx_rw_min_trx_id | ( | void | ) |
Returns the minimum trx id in rw trx list. This is the smallest id for which the trx can possibly be active. (But, you must look at the trx->state to find out if the minimum trx id transaction itself is active, or already committed.)
- Returns
- the minimum trx id, or trx_sys->max_trx_id if the trx list is empty
Returns the minimum trx id in rw trx list. This is the smallest id for which the rw trx can possibly be active. (But, you must look at the trx->state to find out if the minimum trx id transaction itself is active, or already committed.)
- Returns
- the minimum trx id, or trx_sys->max_trx_id if rw trx list is empty
| UNIV_INTERN void trx_sys_close | ( | void | ) |
Shutdown/Close the transaction system.
| UNIV_INTERN void trx_sys_create | ( | void | ) |
Creates the trx_sys instance and initializes ib_bh and mutex.
| UNIV_INTERN ulint trx_sys_create_rsegs | ( | ulint | n_spaces, |
| ulint | n_rsegs | ||
| ) |
number of rollback segments to create
- Parameters
-
n_spaces number of tablespaces for UNDO logs
| UNIV_INTERN void trx_sys_create_sys_pages | ( | void | ) |
Creates and initializes the transaction system at the database creation.
| UNIV_INTERN void trx_sys_file_format_close | ( | void | ) |
Closes the tablespace tag system.
| UNIV_INTERN const char * trx_sys_file_format_id_to_name | ( | const ulint | id | ) |
Get the name representation of the file format from its id.
- Returns
- pointer to the name in: id of the file format
| UNIV_INTERN void trx_sys_file_format_init | ( | void | ) |
Initializes the tablespace tag system.
| UNIV_INTERN dberr_t trx_sys_file_format_max_check | ( | ulint | max_format_id | ) |
Check for the max file format tag stored on disk.
- Returns
- DB_SUCCESS or error code in: the max format id to check
| UNIV_INTERN const char* trx_sys_file_format_max_get | ( | void | ) |
Get the name representation of the file format from its id.
- Returns
- pointer to the max format name
| UNIV_INTERN ibool trx_sys_file_format_max_set | ( | ulint | format_id, |
| const char ** | name | ||
| ) |
Set the file format id unconditionally except if it's already the same value.
- Returns
- TRUE if value updated out: max file format name or NULL if not needed.
- Parameters
-
format_id in: file format id
| UNIV_INTERN ibool trx_sys_file_format_max_upgrade | ( | const char ** | name, |
| ulint | format_id | ||
| ) |
Update the file format tag in the system tablespace only if the given format id is greater than the known max id.
- Returns
- TRUE if format_id was bigger than the known max id in: file format identifier
- Parameters
-
name out: max file format name
| UNIV_INTERN void trx_sys_file_format_tag_init | ( | void | ) |
Tags the system table space with minimum format id if it has not been tagged yet. WARNING: This function is only called during the startup and AFTER the redo log application during recovery has finished.
| UNIV_INLINE trx_id_t trx_sys_get_max_trx_id | ( | void | ) |
Determines the maximum transaction id.
- Returns
- maximum currently allocated trx id; will be stale after the next call to trx_sys_get_new_trx_id()
| UNIV_INLINE ulint trx_sys_get_n_rw_trx | ( | void | ) |
Get the number of transaction in the system, independent of their state.
- Returns
- count of transactions in trx_sys_t::trx_list
Get the number of transaction in the system, independent of their state.
- Returns
- count of transactions in trx_sys_t::rw_trx_list
| UNIV_INLINE trx_id_t trx_sys_get_new_trx_id | ( | void | ) |
Allocates a new transaction id.
- Returns
- new, allocated trx id
| UNIV_INLINE trx_rseg_t* trx_sys_get_nth_rseg | ( | trx_sys_t * | sys, |
| ulint | n | ||
| ) |
Gets the pointer in the nth slot of the rseg array.
- Returns
- pointer to rseg object, NULL if slot not in use in: index of slot
Gets the pointer in the nth slot of the rseg array.
- Returns
- pointer to rseg object, NULL if slot not in use
- Parameters
-
sys in: trx system n in: index of slot
| UNIV_INLINE ibool trx_sys_hdr_page | ( | ulint | space, |
| ulint | page_no | ||
| ) |
Checks if a page address is the trx sys header page.
- Returns
- TRUE if trx sys header page in: page number
Checks if a page address is the trx sys header page.
- Returns
- TRUE if trx sys header page
- Parameters
-
space in: space page_no in: page number
| UNIV_INTERN ib_bh_t* trx_sys_init_at_db_start | ( | void | ) |
Creates and initializes the central memory structures for the transaction system. This is called when the database is started.
- Returns
- min binary heap of rsegs to purge
| UNIV_INTERN void trx_sys_print_mysql_binlog_offset | ( | void | ) |
Prints to stderr the MySQL binlog offset info in the trx system header if the magic number shows it valid.
| UNIV_INTERN void trx_sys_print_mysql_master_log_pos | ( | void | ) |
Prints to stderr the MySQL master log offset info in the trx system header if the magic number shows it valid.
| UNIV_INTERN void trx_sys_update_mysql_binlog_offset | ( | const char * | file_name, |
| ib_int64_t | offset, | ||
| ulint | field, | ||
| mtr_t * | mtr | ||
| ) |
Updates the offset information about the end of the MySQL binlog entry which corresponds to the transaction just being committed. In a MySQL replication slave updates the latest master binlog position up to which replication has proceeded. in: mtr
- Parameters
-
file_name in: MySQL log file name offset in: position in that log file field in: offset of the MySQL log info field in the trx sys header
| UNIV_INTERN ibool trx_sys_validate_trx_list | ( | void | ) |
Validate the trx_sys_t::trx_list.
| UNIV_INLINE trx_sysf_t* trx_sysf_get | ( | mtr_t * | mtr | ) |
Gets a pointer to the transaction system file copy and x-locks its page.
- Returns
- pointer to system file copy, page x-locked in: mtr
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
| UNIV_INTERN ulint trx_sysf_rseg_find_free | ( | mtr_t * | mtr | ) |
Looks for a free slot for a rollback segment in the trx system file copy.
- Returns
- slot index or ULINT_UNDEFINED if not found in: mtr
| UNIV_INLINE ulint trx_sysf_rseg_get_page_no | ( | trx_sysf_t * | sys_header, |
| ulint | i, | ||
| mtr_t * | mtr | ||
| ) |
Gets the page number of the nth rollback segment slot in the trx system file copy.
- Returns
- page number, FIL_NULL if slot unused in: mtr
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 i in: slot index == rseg id mtr in: mtr
| UNIV_INLINE ulint trx_sysf_rseg_get_space | ( | trx_sysf_t * | sys_header, |
| ulint | i, | ||
| mtr_t * | mtr | ||
| ) |
Gets the space of the nth rollback segment slot in the trx system file copy.
- Returns
- space id in: mtr
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 i in: slot index == rseg id mtr in: mtr
| UNIV_INLINE void trx_sysf_rseg_set_page_no | ( | trx_sysf_t * | sys_header, |
| ulint | i, | ||
| ulint | page_no, | ||
| mtr_t * | mtr | ||
| ) |
Sets the page number of the nth rollback segment slot in the trx system file copy. in: mtr
Sets the page number of the nth rollback segment slot in the trx system header.
- Parameters
-
sys_header in: trx sys header i in: slot index == rseg id page_no in: page number, FIL_NULL if the slot is reset to unused mtr in: mtr
| UNIV_INLINE void trx_sysf_rseg_set_space | ( | trx_sysf_t * | sys_header, |
| ulint | i, | ||
| ulint | space, | ||
| mtr_t * | mtr | ||
| ) |
Sets the space id of the nth rollback segment slot in the trx system file copy. in: mtr
Sets the space id of the nth rollback segment slot in the trx system file copy.
- Parameters
-
sys_header in: trx sys file copy i in: slot index == rseg id space in: space id mtr in: mtr
| UNIV_INLINE void trx_write_trx_id | ( | byte * | ptr, |
| trx_id_t | id | ||
| ) |
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_... in: id
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_t* trx_sys |
The transaction system
| char trx_sys_mysql_bin_log_name[] |
If this MySQL server uses binary logging, after InnoDB has been inited
and if it has done a crash recovery, we store the binlog file name and position here. Binlog file name
| ib_int64_t trx_sys_mysql_bin_log_pos |
Binlog file position, or -1 if unknown
| char trx_sys_mysql_master_log_name[] |
In a MySQL replication slave, in crash recovery we store the master log
file name and position here. Master binlog file name
| ib_int64_t trx_sys_mysql_master_log_pos |
Master binlog file position. We have successfully got the updates
up to this position. -1 means that no crash recovery was needed, or there was no master log position info inside InnoDB.
