Reduced doublewrite implementation. More...

Inheritance diagram for Reduced_double_write:

Public Member Functions
	Reduced_double_write (uint16_t id, uint32_t n_pages)
	Constructor. More...

	~Reduced_double_write () override
	Destructor. More...

virtual uint16_t	write_dblwr_pages (buf_flush_t flush_type) noexcept override
	Process the requests in the flush queue, write the space_id, page_id, LSN to the reduced double write file (.bdblwr), sync the file if required and then write to the data files. More...

dberr_t	allocate ()
	Allocate a temporary buffer for writing page entries. More...

Public Member Functions inherited from Double_write
	Double_write (uint16_t id, uint32_t n_pages) noexcept
	Constructor. More...

virtual	~Double_write () noexcept
	Destructor. More...

uint16_t	id () const noexcept

void	write (buf_flush_t flush_type) noexcept
	Process the requests in the flush queue, write the blocks to the double write file, sync the file if required and then write to the data files. More...

bool	wait_for_pending_batch () noexcept
	Wait for any pending batch to complete. More...

bool	flush_to_disk (buf_flush_t flush_type) noexcept
	Flush buffered pages to disk, clear the buffers. More...

void	write_pages (buf_flush_t flush_type) noexcept
	Process the requests in the flush queue, write the blocks to the double write file, sync the file if required and then write to the data files. More...

void	write_data_pages (buf_flush_t flush_type, uint16_t batch_id) noexcept

void	force_flush (buf_flush_t flush_type) noexcept
	Force a flush of the page queue. More...

void	enqueue (buf_flush_t flush_type, buf_page_t bpage, const file::Block e_block) noexcept
	Add a page to the flush batch. More...

void	batch_started () noexcept
	Note that the IO batch has started. More...

void	batch_completed () noexcept
	Wake up all the threads that were waiting for the batch to complete. More...

	Double_write (const Double_write &)=delete

	Double_write (const Double_write &&)=delete

Double_write &	operator= (Double_write &&)=delete

Double_write &	operator= (const Double_write &)=delete

Private Member Functions
void	clear ()
	Clear the temporary buffer used for writing reduced dblwr page. More...

void	create_header (uint32_t batch_id, uint32_t checksum, uint16_t data_len, buf_flush_t flush_type)
	Create Reduced dblwr page header. More...

uint32_t	calculate_checksum (uint16_t data_len)
	Calculate checksum for the Reduced dblwr page. More...

Private Attributes
byte *	m_buf
	Un-aligned temporary buffer. More...

byte *	m_page
	aligned temporary buffer. More...

Additional Inherited Members
Static Public Member Functions inherited from Double_write
static Double_write *	instance (buf_flush_t flush_type, uint32_t buf_pool_index, bool is_reduced) noexcept

static dberr_t	create_batch_segments (uint32_t segments_per_file) noexcept
	Create the batch write segments. More...

static dberr_t	create_reduced_batch_segments () noexcept
	Create the Reduced batch write segments. More...

static dberr_t	create_single_segments () noexcept
	Create the single page flush segments. More...

static void	submit (buf_flush_t flush_type, buf_page_t bpage, const file::Block e_block) noexcept
	Get the instance that handles a particular page's IO. More...

static dberr_t	sync_page_flush (buf_page_t bpage, file::Block e_block) noexcept
	Writes a single page to the doublewrite buffer on disk, syncs it, then writes the page to the datafile. More...

static Double_write *	instance (buf_flush_t flush_type, const buf_page_t *bpage) noexcept

static void	write_complete (buf_page_t *bpage, buf_flush_t flush_type) noexcept
	Updates the double write buffer when a write request is completed. More...

static bool	init_v1 (page_no_t &block1, page_no_t &block2) noexcept
	REad the V1 doublewrite buffer extents boundaries. More...

static bool	create_v1 (page_no_t &block1, page_no_t &block2) noexcept
	Creates the V1 doublewrite buffer extents. More...

static dberr_t	write_to_datafile (const buf_page_t in_bpage, bool sync, const file::Block e_block) noexcept
	Writes a page that has already been written to the doublewrite buffer to the data file. More...

static void	force_flush (buf_flush_t flush_type, uint32_t buf_pool_index) noexcept
	Force a flush of the page queue. More...

static dberr_t	load (dblwr::File &file, recv::Pages *pages) noexcept
	Load the doublewrite buffer pages from an external file. More...

static dberr_t	load_reduced_batch (dblwr::File &file, recv::Pages *pages) noexcept
	Load the reduced doublewrite buffer page entries from an reduced batch double write buffer file (.bdblwr) More...

static dberr_t	init_file (dblwr::File &file, uint32_t n_pages, uint32_t phy_size=univ_page_size.physical()) noexcept
	Write zeros to the file if it is "empty". More...

static void	reset_file (dblwr::File &file, bool truncate) noexcept
	Reset the size in bytes to the configured size. More...

static void	reduced_reset_file (dblwr::File &file, uint32_t pages_per_file, uint32_t phy_size) noexcept
	Reset the size in bytes to the configured size. More...

static void	reset_files () noexcept
	Reset the size in bytes to the configured size of all files. More...

static dberr_t	create_v2 () noexcept
	Create the v2 data structures. More...

static dberr_t	create_reduced () noexcept
	Create the data structures for reduced doublewrite buffer. More...

static bool	is_fsync_required () noexcept

static void	prepare (const buf_page_t bpage, void ptr, uint32_t len) noexcept
	Extract the data and length to write to the doublewrite file. More...

static void	shutdown () noexcept
	Free the data structures. More...

static void	toggle (ulong value) noexcept
	Toggle the doublewrite buffer dynamically. More...

static void	single_write (Segment segment, const buf_page_t bpage, file::Block *e_block) noexcept
	Write the data to disk synchronously. More...

Public Attributes inherited from Double_write
unsigned long long	m_bytes_written {}
	Number of bytes written to disk by this instance. More...

Static Public Attributes inherited from Double_write
static uint32_t	s_n_instances {}
	Number of instances. More...

static std::vector< dblwr::File >	s_files
	Files to use for atomic writes. More...

static std::vector< dblwr::File >	s_r_files
	Reduced batch doublewrite files to use for atomic writes. More...

static Instances *	s_instances {}
	The global instances. More...

static Instances *	s_r_instances {}
	The global Reduced Doublewrite instances. More...

Protected Types inherited from Double_write
using	Segments = mpmc_bq< Segment * >

using	Instances = std::vector< Double_write * >

using	Batch_segments = mpmc_bq< Batch_segment * >

Static Protected Member Functions inherited from Double_write
static void	free_segments (Batch_segments *&segments) noexcept
	Utility function to free batch segments. More...

static bool	is_reduced_batch_id (uint32_t batch_id)

Protected Attributes inherited from Double_write
uint16_t	m_id {}
	Instance ID. More...

ib_mutex_t	m_mutex
	Protects m_buf_pages. More...

os_event_t	m_event
	Wait for IO batch to complete. More...

std::atomic_bool	m_batch_running {false}
	true if the the batch hasn't completed yet. More...

Buffer	m_buffer
	The copy of the page frame, the page must be in in m_buf_pages. More...

Buf_pages	m_buf_pages
	Pages that should be written to the data files. More...

Static Protected Attributes inherited from Double_write
static Batch_segments *	s_LRU_batch_segments {}
	File segments to use for LRU batched writes. More...

static Batch_segments *	s_flush_list_batch_segments {}
	File segments to use for flush list batched writes. More...

static Segments *	s_single_segments {}
	File segments to use for single page writes. More...

static Batch_segments *	s_r_LRU_batch_segments {}
	File segments to use for LRU batched writes in reduced dblwr mode. More...

static Batch_segments *	s_r_flush_list_batch_segments {}
	File segments to use for flush list batched writes (reduced mode) More...

static std::vector< Batch_segment * >	s_segments {}
	For indexing batch segments by ID. More...

static uint32_t	s_regular_last_batch_id {}
	Last used batch_id for regular batch segments. More...

Detailed Description

Reduced doublewrite implementation.

Uses separate .bdblwr files and can coexist with regular doublewrite buffer implementation

Constructor & Destructor Documentation

◆ Reduced_double_write()

Reduced_double_write::Reduced_double_write	(	uint16_t	id,
		uint32_t	n_pages
	)

inline

Constructor.

Parameters

[in]	id	Instance ID
[in]	n_pages	Number of pages handled by this instance.

◆ ~Reduced_double_write()

Reduced_double_write::~Reduced_double_write ( )

inlineoverride

Destructor.

Member Function Documentation

◆ allocate()

dberr_t Reduced_double_write::allocate ( )

Allocate a temporary buffer for writing page entries.

Returns: DB_SUCCESS on success, error code on failure.

◆ calculate_checksum()

uint32_t Reduced_double_write::calculate_checksum ( uint16_t data_len )

inlineprivate

Calculate checksum for the Reduced dblwr page.

Parameters

[in] data_len amount of data in page

Returns: checksum calcuated

◆ clear()

void Reduced_double_write::clear ( )

inlineprivate

Clear the temporary buffer used for writing reduced dblwr page.

◆ create_header()

void Reduced_double_write::create_header	(	uint32_t	batch_id,
		uint32_t	checksum,
		uint16_t	data_len,
		buf_flush_t	flush_type
	)

inlineprivate

Create Reduced dblwr page header.

Parameters

[in]	batch_id	Batch_id of the Reduced dblwr segment
[in]	checksum	Checksum of the page
[in]	data_len	Length of data in page
[in]	flush_type	LRU of FLUSH_LIST type

◆ write_dblwr_pages()

uint16_t Reduced_double_write::write_dblwr_pages ( buf_flush_t flush_type )

overridevirtualnoexcept

Process the requests in the flush queue, write the space_id, page_id, LSN to the reduced double write file (.bdblwr), sync the file if required and then write to the data files.

Parameters

[in] flush_type LRU or FLUSH request.

Reimplemented from Double_write.

Member Data Documentation

◆ m_buf

byte* Reduced_double_write::m_buf

private

Un-aligned temporary buffer.

◆ m_page

byte* Reduced_double_write::m_page

private

aligned temporary buffer.

Created from m_buf

The documentation for this class was generated from the following file:

storage/innobase/buf/buf0dblwr.cc

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Reduced_double_write()

◆ ~Reduced_double_write()

Member Function Documentation

◆ allocate()

◆ calculate_checksum()

◆ clear()

◆ create_header()

◆ write_dblwr_pages()

Member Data Documentation

◆ m_buf

◆ m_page