mtr0log.h File Reference

Mini-transaction logging routines. More...

#include "dyn0buf.h"
#include "mtr0mtr.h"
#include "univ.i"
#include "mtr0log.ic"

Go to the source code of this file.

Macros
#define	COMPACT_FLAG   0x01
#define	VERSION_FLAG   0x02
#define	INSTANT_FLAG   0x04
#define	IS_INSTANT(flags)   (flags & INSTANT_FLAG)
#define	IS_VERSIONED(flags)   (flags & VERSION_FLAG)
#define	IS_COMPACT(flags)   (flags & COMPACT_FLAG)
#define	SET_INSTANT(flags)   (flag |= INSTANT_FLAG)
#define	SET_VERSIONED(flags)   (flag |= VERSION_FLAG)
#define	SET_COMPACT(flags)   (flag |= COMPACT_FLAG)

Functions
void	mlog_write_ulint (byte *ptr, ulint val, mlog_id_t type, mtr_t *mtr)
	Writes 1, 2 or 4 bytes to a file page. More...
void	mlog_write_ull (byte *ptr, uint64_t val, mtr_t *mtr)
	Writes 8 bytes to a file page. More...
void	mlog_write_string (byte *ptr, const byte *str, ulint len, mtr_t *mtr)
	Writes a string to a file page buffered in the buffer pool. More...
void	mlog_log_string (byte *ptr, ulint len, mtr_t *mtr)
	Logs a write of a string to a file page buffered in the buffer pool. More...
void	mlog_write_initial_log_record (const byte *ptr, mlog_id_t type, mtr_t *mtr)
	Writes initial part of a log record consisting of one-byte item type and four-byte space and page numbers. More...
static void	mlog_catenate_ulint (mtr_buf_t *dyn_buf, ulint val, mlog_id_t type)
	Catenates 1 - 4 bytes to the mtr log. More...
static void	mlog_catenate_ulint (mtr_t *mtr, ulint val, mlog_id_t type)
	Catenates 1 - 4 bytes to the mtr log. More...
void	mlog_catenate_string (mtr_t *mtr, const byte *str, ulint len)
	Catenates n bytes to the mtr log. More...
static void	mlog_catenate_ulint_compressed (mtr_t *mtr, ulint val)
	Catenates a compressed ulint to mlog. More...
static void	mlog_catenate_ull_compressed (mtr_t *mtr, uint64_t val)
	Catenates a compressed 64-bit integer to mlog. More...
static bool	mlog_open (mtr_t *mtr, ulint size, byte *&buffer)
	Opens a buffer to mlog. More...
static bool	mlog_open_metadata (mtr_t *mtr, ulint size, byte *&buffer)
	Opens a buffer to mlog. More...
static void	mlog_close (mtr_t *mtr, byte *ptr)
	Closes a buffer opened to mlog. More...
static byte *	mlog_write_initial_dict_log_record (mlog_id_t type, table_id_t id, uint64_t version, byte *log_ptr, mtr_t *mtr)
	Writes a log record about a dictionary operation, which would cost at most 23 bytes. More...
static byte *	mlog_write_initial_log_record_low (mlog_id_t type, space_id_t space_id, page_no_t page_no, byte *log_ptr, mtr_t *mtr)
	Writes a log record about an operation. More...
static byte *	mlog_write_initial_log_record_fast (const byte *ptr, mlog_id_t type, byte *log_ptr, mtr_t *mtr)
	Writes the initial part of a log record (3..11 bytes). More...
byte *	mlog_parse_initial_dict_log_record (const byte *ptr, const byte *end_ptr, mlog_id_t *type, table_id_t *id, uint64_t *version)
	Parses an initial log record written by mlog_write_initial_dict_log_record. More...
byte *	mlog_parse_initial_log_record (const byte *ptr, const byte *end_ptr, mlog_id_t *type, space_id_t *space, page_no_t *page_no)
	Parses an initial log record written by mlog_write_initial_log_record. More...
byte *	mlog_parse_nbytes (mlog_id_t type, const byte *ptr, const byte *end_ptr, byte *page, void *page_zip)
	Parses a log record written by mlog_write_ulint or mlog_write_ull. More...
byte *	mlog_parse_string (byte *ptr, byte *end_ptr, byte *page, void *page_zip)
	Parses a log record written by mlog_write_string. More...
bool	mlog_open_and_write_index (mtr_t *mtr, const byte *rec, const dict_index_t *index, mlog_id_t type, size_t size, byte *&log_ptr)
	Opens a buffer for mlog, writes the initial log record and, if needed, the field lengths of an index. More...
byte *	mlog_parse_index (byte *ptr, const byte *end_ptr, dict_index_t **index)
	Parses a log record written by mlog_open_and_write_index. More...
byte *	mlog_parse_index_8027 (byte *ptr, const byte *end_ptr, bool comp, dict_index_t **index)
	Parses a log record written by mlog_open_and_write_index in version <= 8027. More...

Variables
constexpr uint8_t	INDEX_LOG_VERSION_0 = 0
constexpr uint8_t	INDEX_LOG_VERSION_CURRENT = 1
constexpr uint8_t	INDEX_LOG_VERSION_MAX = INDEX_LOG_VERSION_CURRENT
constexpr size_t	REDO_LOG_INITIAL_INFO_SIZE = 11
constexpr auto	MLOG_BUF_MARGIN = 256
	Insert, update, and maybe other functions may use this value to define an extra mlog buffer size for variable size data. More...

Detailed Description

Mini-transaction logging routines.

Created 12/7/1995 Heikki Tuuri

Macro Definition Documentation

COMPACT_FLAG

#define COMPACT_FLAG   0x01

INSTANT_FLAG

#define INSTANT_FLAG   0x04

IS_COMPACT

#define IS_COMPACT

(

flags

)

(flags & COMPACT_FLAG)

IS_INSTANT

#define IS_INSTANT

(

flags

)

(flags & INSTANT_FLAG)

IS_VERSIONED

#define IS_VERSIONED

(

flags

)

(flags & VERSION_FLAG)

SET_COMPACT

#define SET_COMPACT

(

flags

)

(flag |= COMPACT_FLAG)

SET_INSTANT

#define SET_INSTANT

(

flags

)

(flag |= INSTANT_FLAG)

SET_VERSIONED

#define SET_VERSIONED

(

flags

)

(flag |= VERSION_FLAG)

VERSION_FLAG

#define VERSION_FLAG   0x02

Function Documentation

mlog_catenate_string()

void mlog_catenate_string	(	mtr_t *	mtr,
		const byte *	str,
		ulint	len
	)

Catenates n bytes to the mtr log.

Parameters

[in]	mtr	Mini-transaction
[in]	str	String to write
[in]	len	String length

mlog_catenate_ulint() [1/2]

static void mlog_catenate_ulint ( mtr_buf_t *  dyn_buf, ulint  val, mlog_id_t  type  )

inlinestatic

Catenates 1 - 4 bytes to the mtr log.

The value is not compressed.

Parameters

[in,out]	dyn_buf	buffer to write
[in]	val	value to write
[in]	type	type of value to write

mlog_catenate_ulint() [2/2]

static void mlog_catenate_ulint ( mtr_t *  mtr, ulint  val, mlog_id_t  type  )

inlinestatic

Catenates 1 - 4 bytes to the mtr log.

Parameters

[in]	mtr	mtr
[in]	val	value to write
[in]	type	MLOG_1BYTE, MLOG_2BYTES, MLOG_4BYTES

mlog_catenate_ulint_compressed()

static void mlog_catenate_ulint_compressed ( mtr_t *  mtr, ulint  val  )

inlinestatic

Catenates a compressed ulint to mlog.

Parameters

[in]	mtr	mtr
[in]	val	value to write

mlog_catenate_ull_compressed()

static void mlog_catenate_ull_compressed ( mtr_t *  mtr, uint64_t  val  )

inlinestatic

Catenates a compressed 64-bit integer to mlog.

Parameters

[in]	mtr	mtr
[in]	val	value to write

mlog_close()

static void mlog_close ( mtr_t *  mtr, byte *  ptr  )

inlinestatic

Closes a buffer opened to mlog.

Parameters

[in]	mtr	mtr
[in]	ptr	buffer space from ptr up was not used

mlog_log_string()

void mlog_log_string	(	byte *	ptr,
		ulint	len,
		mtr_t *	mtr
	)

Logs a write of a string to a file page buffered in the buffer pool.

Writes the corresponding log record to the mini-transaction log. in: mini-transaction handle

Writes the corresponding log record to the mini-transaction log.

Parameters

ptr	in: pointer written to
len	in: string length
mtr	in: mini-transaction handle

mlog_open()

static bool mlog_open ( mtr_t *  mtr, ulint  size, byte *&  buffer  )

inlinestatic

Opens a buffer to mlog.

It must be closed with mlog_close.

Parameters

[in,out]	mtr	mtr
[in]	size	buffer size in bytes; MUST be smaller than DYN_ARRAY_DATA_SIZE!
[out]	buffer	mlog buffer pointer if opened successfully

Return values

true	if opened successfully.
false	if not opened. One case is when redo is disabled for mtr.

mlog_open_and_write_index()

bool mlog_open_and_write_index	(	mtr_t *	mtr,
		const byte *	rec,
		const dict_index_t *	index,
		mlog_id_t	type,
		size_t	size,
		byte *&	log_ptr
	)

Opens a buffer for mlog, writes the initial log record and, if needed, the field lengths of an index.

Reserves space for further log entries. The log entry must be closed with mtr_close().

Parameters

[in,out]	mtr	Mini-transaction
[in]	rec	Index record or page
[in]	index	Record descriptor
[in]	type	Log item type
[in]	size	Requested buffer size in bytes. if 0, calls mlog_close() and returns false.
[out]	log_ptr	Log buffer pointer

Return values

true	if opened successfully.
false	if not opened. One case is when redo is disabled for mtr.

mlog_open_metadata()

static bool mlog_open_metadata ( mtr_t *  mtr, ulint  size, byte *&  buffer  )

inlinestatic

Opens a buffer to mlog.

It must be closed with mlog_close. This is used for writing log for metadata changes

Parameters

[in,out]	mtr	mtr
[in]	size	buffer size in bytes; MUST be smaller than DYN_ARRAY_DATA_SIZE!
[out]	buffer	mlog buffer pointer if opened successfully

Return values

true	if opened successfully.
false	if not opened. One case is when redo is disabled for mtr.

mlog_parse_index()

byte * mlog_parse_index	(	byte *	ptr,
		const byte *	end_ptr,
		dict_index_t **	index
	)

Parses a log record written by mlog_open_and_write_index.

Parameters

[in]	ptr	buffer
[in]	end_ptr	buffer end
[out]	index	own: dummy index

Returns

parsed record end, NULL if not a complete record

mlog_parse_index_8027()

byte * mlog_parse_index_8027	(	byte *	ptr,
		const byte *	end_ptr,
		bool	comp,
		dict_index_t **	index
	)

Parses a log record written by mlog_open_and_write_index in version <= 8027.

This function should never be changed and should be removed once recovery from mysql-8.0.27 is not needed anymore.

Parameters

[in]	ptr	buffer
[in]	end_ptr	buffer end
[in]	comp	true=compact row format
[out]	index	own: dummy index

Returns

parsed record end, NULL if not a complete record

mlog_parse_initial_dict_log_record()

byte * mlog_parse_initial_dict_log_record	(	const byte *	ptr,
		const byte *	end_ptr,
		mlog_id_t *	type,
		table_id_t *	id,
		uint64_t *	version
	)

Parses an initial log record written by mlog_write_initial_dict_log_record.

Parameters

[in]	ptr	buffer
[in]	end_ptr	buffer end
[out]	type	log record type, should be MLOG_TABLE_DYNAMIC_META
[out]	id	table id
[out]	version	table dynamic metadata version

Returns

parsed record end, NULL if not a complete record

mlog_parse_initial_log_record()

byte * mlog_parse_initial_log_record	(	const byte *	ptr,
		const byte *	end_ptr,
		mlog_id_t *	type,
		space_id_t *	space,
		page_no_t *	page_no
	)

Parses an initial log record written by mlog_write_initial_log_record.

Returns

parsed record end, NULL if not a complete record out: page number

parsed record end, NULL if not a complete record

Parameters

ptr	in: buffer
end_ptr	in: buffer end
type	out: log record type: MLOG_1BYTE, ...
space	out: space id
page_no	out: page number

mlog_parse_nbytes()

byte * mlog_parse_nbytes	(	mlog_id_t	type,
		const byte *	ptr,
		const byte *	end_ptr,
		byte *	page,
		void *	page_zip
	)

Parses a log record written by mlog_write_ulint or mlog_write_ull.

Returns

parsed record end, NULL if not a complete record in/out: compressed page, or NULL

parsed record end, NULL if not a complete record or a corrupt record

Parameters

type	in: log record type: MLOG_1BYTE, ...
ptr	in: buffer
end_ptr	in: buffer end
page	in: page where to apply the log record, or NULL
page_zip	in/out: compressed page, or NULL

mlog_parse_string()

byte * mlog_parse_string	(	byte *	ptr,
		byte *	end_ptr,
		byte *	page,
		void *	page_zip
	)

Parses a log record written by mlog_write_string.

Returns

parsed record end, NULL if not a complete record in/out: compressed page, or NULL

parsed record end, NULL if not a complete record

Parameters

ptr	in: buffer
end_ptr	in: buffer end
page	in: page where to apply the log record, or NULL
page_zip	in/out: compressed page, or NULL

mlog_write_initial_dict_log_record()

static byte * mlog_write_initial_dict_log_record ( mlog_id_t  type, table_id_t  id, uint64_t  version, byte *  log_ptr, mtr_t *  mtr  )

inlinestatic

Writes a log record about a dictionary operation, which would cost at most 23 bytes.

Parameters

[in]	type	Redo log record type
[in]	id	Table id
[in]	version	Table dynamic metadata version
[in,out]	log_ptr	Current end of mini-transaction log
[in,out]	mtr	Mini-transaction

Returns

end of mini-transaction log

mlog_write_initial_log_record()

void mlog_write_initial_log_record	(	const byte *	ptr,
		mlog_id_t	type,
		mtr_t *	mtr
	)

Writes initial part of a log record consisting of one-byte item type and four-byte space and page numbers.

in: mini-transaction handle

Writes initial part of a log record consisting of one-byte item type and four-byte space and page numbers.

Also pushes info to the mtr memo that a buffer page has been modified.

Parameters

ptr	in: pointer to (inside) a buffer frame holding the file page where modification is made
type	in: log item type: MLOG_1BYTE, ...
mtr	in: mini-transaction handle

mlog_write_initial_log_record_fast()

static byte * mlog_write_initial_log_record_fast ( const byte *  ptr, mlog_id_t  type, byte *  log_ptr, mtr_t *  mtr  )

inlinestatic

Writes the initial part of a log record (3..11 bytes).

If the implementation of this function is changed, all size parameters to mlog_open() should be adjusted accordingly!

Parameters

[in]	ptr	pointer to (inside) a buffer frame holding the file page where modification is made
[in]	type	log item type: MLOG_1BYTE, ...
[in]	log_ptr	pointer to mtr log which has been opened
[in]	mtr	mtr

Returns

new value of log_ptr

mlog_write_initial_log_record_low()

static byte * mlog_write_initial_log_record_low ( mlog_id_t  type, space_id_t  space_id, page_no_t  page_no, byte *  log_ptr, mtr_t *  mtr  )

inlinestatic

Writes a log record about an operation.

Parameters

[in]	type	Redo log record type
[in]	space_id	Tablespace identifier
[in]	page_no	Page number
[in,out]	log_ptr	Current end of mini-transaction log
[in,out]	mtr	Mini-transaction

Returns

end of mini-transaction log

mlog_write_string()

void mlog_write_string	(	byte *	ptr,
		const byte *	str,
		ulint	len,
		mtr_t *	mtr
	)

Writes a string to a file page buffered in the buffer pool.

Writes the corresponding log record to the mini-transaction log. in: mini-transaction handle

Writes the corresponding log record to the mini-transaction log.

Parameters

ptr	in: pointer where to write
str	in: string to write
len	in: string length
mtr	in: mini-transaction handle

mlog_write_ulint()

void mlog_write_ulint	(	byte *	ptr,
		ulint	val,
		mlog_id_t	type,
		mtr_t *	mtr
	)

Writes 1, 2 or 4 bytes to a file page.

Writes the corresponding log record to the mini-transaction log if mtr is not NULL. in: mini-transaction handle

Writes the corresponding log record to the mini-transaction log if mtr is not NULL.

Parameters

ptr	in: pointer where to write
val	in: value to write
type	in: MLOG_1BYTE, MLOG_2BYTES, MLOG_4BYTES
mtr	in: mini-transaction handle

mlog_write_ull()

void mlog_write_ull	(	byte *	ptr,
		uint64_t	val,
		mtr_t *	mtr
	)

Writes 8 bytes to a file page.

Writes the corresponding log record to the mini-transaction log, only if mtr is not NULL in: mini-transaction handle

Writes the corresponding log record to the mini-transaction log, only if mtr is not NULL

Parameters

ptr	in: pointer where to write
val	in: value to write
mtr	in: mini-transaction handle

Variable Documentation

INDEX_LOG_VERSION_0

constexpr uint8_t INDEX_LOG_VERSION_0 = 0

constexpr

INDEX_LOG_VERSION_CURRENT

constexpr uint8_t INDEX_LOG_VERSION_CURRENT = 1

constexpr

INDEX_LOG_VERSION_MAX

constexpr uint8_t INDEX_LOG_VERSION_MAX = INDEX_LOG_VERSION_CURRENT

constexpr

MLOG_BUF_MARGIN

constexpr auto MLOG_BUF_MARGIN = 256

constexpr

Insert, update, and maybe other functions may use this value to define an extra mlog buffer size for variable size data.

REDO_LOG_INITIAL_INFO_SIZE

constexpr size_t REDO_LOG_INITIAL_INFO_SIZE = 11

constexpr