buf0dump.cc File Reference

Implements a buffer pool dump/load. More...

#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <algorithm>
#include "buf0buf.h"
#include "buf0dump.h"
#include "dict0dict.h"
#include "my_io.h"
#include "my_psi_config.h"
#include "my_sys.h"
#include "my_thread.h"
#include "mysql/psi/mysql_stage.h"
#include "os0file.h"
#include "os0thread-create.h"
#include "os0thread.h"
#include "srv0srv.h"
#include "srv0start.h"
#include "sync0rw.h"
#include "univ.i"
#include "ut0byte.h"

Macros
#define	SHOULD_QUIT()   (SHUTTING_DOWN() && obey_shutdown)

Typedefs
typedef uint64_t	buf_dump_t

Enumerations
enum	status_severity { STATUS_VERBOSE , STATUS_INFO , STATUS_ERR }

Functions
static bool	SHUTTING_DOWN ()
uint64_t	BUF_DUMP_CREATE (space_id_t space, page_no_t page)
constexpr space_id_t	BUF_DUMP_SPACE (uint64_t a)
constexpr page_no_t	BUF_DUMP_PAGE (uint64_t a)
void	buf_dump_start ()
	Wakes up the buffer pool dump/load thread and instructs it to start a dump. More...
void	buf_load_start ()
	Wakes up the buffer pool dump/load thread and instructs it to start a load. More...
static void	buf_dump_status (enum status_severity severity, const char *fmt,...)
	Sets the global variable that feeds MySQL's innodb_buffer_pool_dump_status to the specified string. More...
static void	buf_load_status (enum status_severity severity, const char *fmt,...)
	Sets the global variable that feeds MySQL's innodb_buffer_pool_load_status to the specified string. More...
static const char *	get_buf_dump_dir ()
	Returns the directory path where the buffer pool dump file will be created. More...
void	buf_dump_generate_path (char *path, size_t path_size)
	Generate the path to the buffer pool dump/load file. More...
static void	buf_dump (bool obey_shutdown)
	Perform a buffer pool dump into the file specified by innodb_buffer_pool_filename. More...
static void	buf_load_throttle_if_needed (std::chrono::steady_clock::time_point *last_check_time, ulint *last_activity_count, ulint n_io)
	Artificially delay the buffer pool loading if necessary. More...
static void	buf_load ()
	Perform a buffer pool load from the file specified by innodb_buffer_pool_filename. More...
void	buf_load_abort ()
	Aborts a currently running buffer pool load. More...
void	buf_dump_thread ()
	This is the main thread for buffer pool dump/load. More...

Variables
static bool	buf_dump_should_start = false
static bool	buf_load_should_start = false
static bool	buf_load_abort_flag = false

Detailed Description

Implements a buffer pool dump/load.

Created April 08, 2011 Vasil Dimov

Macro Definition Documentation

SHOULD_QUIT

#define SHOULD_QUIT

(

)

(SHUTTING_DOWN() && obey_shutdown)

Typedef Documentation

buf_dump_t

typedef uint64_t buf_dump_t

Enumeration Type Documentation

status_severity

enum status_severity

Enumerator
STATUS_VERBOSE
STATUS_INFO
STATUS_ERR

Function Documentation

buf_dump()

static void buf_dump ( bool  obey_shutdown )

static

Perform a buffer pool dump into the file specified by innodb_buffer_pool_filename.

If any errors occur then the value of innodb_buffer_pool_dump_status will be set accordingly, see buf_dump_status(). The dump filename can be specified by (relative to srv_data_home): SET GLOBAL innodb_buffer_pool_filename='filename';

Parameters

[in]

obey_shutdown

quit if we are in a shutting down state

BUF_DUMP_CREATE()

uint64_t BUF_DUMP_CREATE ( space_id_t  space, page_no_t  page  )

inline

buf_dump_generate_path()

void buf_dump_generate_path	(	char *	path,
		size_t	path_size
	)

Generate the path to the buffer pool dump/load file.

Parameters

[out]	path	generated path
[in]	path_size	size of 'path', used as in snprintf(3).

BUF_DUMP_PAGE()

constexpr page_no_t BUF_DUMP_PAGE ( uint64_t  a )

constexpr

BUF_DUMP_SPACE()

constexpr space_id_t BUF_DUMP_SPACE ( uint64_t  a )

constexpr

buf_dump_start()

void buf_dump_start

(

)

Wakes up the buffer pool dump/load thread and instructs it to start a dump.

This function is called by MySQL code via buffer_pool_dump_now() and it should return immediately because the whole MySQL is frozen during its execution.

buf_dump_status()

static void buf_dump_status ( enum status_severity  severity, const char *  fmt,   ...  )

static

Sets the global variable that feeds MySQL's innodb_buffer_pool_dump_status to the specified string.

The format and the following parameters are the same as the ones used for printf(3). The value of this variable can be retrieved by: SELECT variable_value FROM performance_schema.global_status WHERE variable_name = 'INNODB_BUFFER_POOL_DUMP_STATUS'; or by: SHOW STATUS LIKE 'innodb_buffer_pool_dump_status';

Parameters

severity	in: status severity
fmt	in: format
...	in: extra parameters according to fmt

buf_dump_thread()

void buf_dump_thread

(

)

This is the main thread for buffer pool dump/load.

It waits for an event and when waked up either performs a dump or load and sleeps again.

buf_load()

static void buf_load ( )

static

Perform a buffer pool load from the file specified by innodb_buffer_pool_filename.

If any errors occur then the value of innodb_buffer_pool_load_status will be set accordingly, see buf_load_status(). The dump filename can be specified by (relative to srv_data_home): SET GLOBAL innodb_buffer_pool_filename='filename';

buf_load_abort()

void buf_load_abort

(

)

Aborts a currently running buffer pool load.

This function is called by MySQL code via buffer_pool_load_abort() and it should return immediately because the whole MySQL is frozen during its execution.

buf_load_start()

void buf_load_start

(

)

Wakes up the buffer pool dump/load thread and instructs it to start a load.

This function is called by MySQL code via buffer_pool_load_now() and it should return immediately because the whole MySQL is frozen during its execution.

buf_load_status()

static void buf_load_status ( enum status_severity  severity, const char *  fmt,   ...  )

static

Sets the global variable that feeds MySQL's innodb_buffer_pool_load_status to the specified string.

The format and the following parameters are the same as the ones used for printf(3). The value of this variable can be retrieved by: SELECT variable_value FROM performance_schema.global_status WHERE variable_name = 'INNODB_BUFFER_POOL_LOAD_STATUS'; or by: SHOW STATUS LIKE 'innodb_buffer_pool_load_status';

Parameters

severity	in: status severity
fmt	in: format
...	in: extra parameters according to fmt

buf_load_throttle_if_needed()

static void buf_load_throttle_if_needed ( std::chrono::steady_clock::time_point *  last_check_time, ulint *  last_activity_count, ulint  n_io  )

inlinestatic

Artificially delay the buffer pool loading if necessary.

The idea of this function is to prevent hogging the server with IO and slowing down too much normal client queries.

Parameters

[in,out]	last_check_time	milliseconds since epoch of the last time we did check if throttling is needed, we do the check every srv_io_capacity IO ops.
[in]	last_activity_count	activity count
[in]	n_io	number of IO ops done since buffer pool load has started

get_buf_dump_dir()

static const char * get_buf_dump_dir ( )

static

Returns the directory path where the buffer pool dump file will be created.

Returns

directory path

SHUTTING_DOWN()

static bool SHUTTING_DOWN ( )

inlinestatic

Variable Documentation

buf_dump_should_start

bool buf_dump_should_start = false

static

buf_load_abort_flag

bool buf_load_abort_flag = false

static

buf_load_should_start

bool buf_load_should_start = false

static