The fragment node represents one fragment. More...

#include <lob0impl.h>

Public Member Functions
	frag_node_t (const plist_node_t &node, mtr_t *mtr)
	Constructor. More...

	frag_node_t (byte frame, byte ptr)

	frag_node_t (byte frame, byte ptr, mtr_t *mtr)
	Constructor. More...

	frag_node_t (byte frame, byte ptr, ulint len, mtr_t *mtr)
	Constructor. More...

byte *	frag_begin () const

byte *	data_begin () const

void	set_total_len (ulint len)

void	incr_length_by_2 ()
	Increment the total length of this fragment by 2 bytes. More...

void	decr_length_by_2 ()
	Decrement the total length of this fragment by 2 bytes. More...

bool	is_before (const frag_node_t &frag) const

void	set_frag_id_null ()

void	set_frag_id (ulint id)

ulint	get_frag_id () const

ulint	payload () const
	Get the space available in this fragment for storing data. More...

ulint	get_total_len () const
	Get the total length of this fragment, including its metadata. More...

paddr_t	addr () const
	Get the offset of the current fragment within page. More...

byte *	ptr () const
	Gets the pointer to the beginning of the current fragment. More...

byte *	end_ptr () const
	Gets the pointer just after the current fragment. More...

byte *	frame () const
	Get the page frame. More...

std::ostream &	print (std::ostream &out) const

frag_node_t	get_next_frag ()

frag_node_t	get_next_node ()

frag_node_t	get_prev_node ()

frag_node_t	get_prev_frag ()

bool	merge (frag_node_t &next)
	Merge the current fragment node with the given next fragment node. More...

bool	is_null () const

bool	is_equal (const frag_node_t &that) const

bool	is_equal (const plist_node_t &node) const

Static Public Member Functions
static ulint	overhead ()
	Amount of space that will be used up by meta data. More...

static ulint	header_size ()
	Only the header size. More...

Public Attributes
plist_node_t	m_node
	The page list node. More...

Static Public Attributes
static const ulint	OFFSET_LEN = plist_node_t::SIZE
	The offset where the length of fragment is stored. More...

static const ulint	OFFSET_FRAG_ID = OFFSET_LEN + 2
	The offset where fragment id is stored. More...

static const ulint	OFFSET_DATA = OFFSET_FRAG_ID + 2
	The offset where fragment data is stored. More...

static const ulint	SIZE_OF_PAGE_DIR_ENTRY = 2
	The size of a page directory entry in a fragment page in bytes. More...

Private Attributes
mtr_t *	m_mtr
	The mini-transaction context. More...

Detailed Description

The fragment node represents one fragment.

Constructor & Destructor Documentation

◆ frag_node_t() [1/4]

lob::frag_node_t::frag_node_t	(	const plist_node_t &	node,
		mtr_t *	mtr
	)

inline

Constructor.

Parameters

[in]	node	Page list node.
[in]	mtr	Mini-transaction.

◆ frag_node_t() [2/4]

lob::frag_node_t::frag_node_t	(	byte *	frame,
		byte *	ptr
	)

inline

◆ frag_node_t() [3/4]

lob::frag_node_t::frag_node_t	(	byte *	frame,
		byte *	ptr,
		mtr_t *	mtr
	)

inline

Constructor.

Parameters

[in]	frame	Page frame where the fragment node is located.
[in]	ptr	Location of fragment node within page frame.
[in]	mtr	Mini-transaction context.

◆ frag_node_t() [4/4]

lob::frag_node_t::frag_node_t	(	byte *	frame,
		byte *	ptr,
		ulint	len,
		mtr_t *	mtr
	)

inline

Constructor.

Parameters

[in]	frame	Page frame where the fragment node is located.
[in]	ptr	Location of fragment node within page frame.
[in]	len	Length of the fragment.
[in]	mtr	Mini-transaction context.

Member Function Documentation

◆ addr()

paddr_t lob::frag_node_t::addr ( ) const

inline

Get the offset of the current fragment within page.

Returns: the offset of the current fragment within.

◆ data_begin()

byte * lob::frag_node_t::data_begin ( ) const

inline

◆ decr_length_by_2()

void lob::frag_node_t::decr_length_by_2 ( )

inline

Decrement the total length of this fragment by 2 bytes.

◆ end_ptr()

byte * lob::frag_node_t::end_ptr ( ) const

inline

Gets the pointer just after the current fragment.

The pointer returned does not belong to this fragment. This is used to check adjacency.

Returns: pointer to the end of the current fragment.

◆ frag_begin()

byte * lob::frag_node_t::frag_begin ( ) const

inline

◆ frame()

byte * lob::frag_node_t::frame ( ) const

inline

Get the page frame.

Returns: the page frame.

◆ get_frag_id()

ulint lob::frag_node_t::get_frag_id ( ) const

inline

◆ get_next_frag()

frag_node_t lob::frag_node_t::get_next_frag ( )

inline

◆ get_next_node()

frag_node_t lob::frag_node_t::get_next_node ( )

inline

◆ get_prev_frag()

frag_node_t lob::frag_node_t::get_prev_frag ( )

inline

◆ get_prev_node()

frag_node_t lob::frag_node_t::get_prev_node ( )

inline

◆ get_total_len()

ulint lob::frag_node_t::get_total_len ( ) const

inline

Get the total length of this fragment, including its metadata.

◆ header_size()

static ulint lob::frag_node_t::header_size ( )

inlinestatic

Only the header size.

Don't include the page dir entry size here.

◆ incr_length_by_2()

void lob::frag_node_t::incr_length_by_2 ( )

inline

Increment the total length of this fragment by 2 bytes.

◆ is_before()

bool lob::frag_node_t::is_before ( const frag_node_t & frag ) const

inline

◆ is_equal() [1/2]

bool lob::frag_node_t::is_equal ( const frag_node_t & that ) const

inline

◆ is_equal() [2/2]

bool lob::frag_node_t::is_equal ( const plist_node_t & node ) const

inline

◆ is_null()

bool lob::frag_node_t::is_null ( ) const

inline

◆ merge()

bool lob::frag_node_t::merge ( frag_node_t & next )

inline

Merge the current fragment node with the given next fragment node.

This will succeed only if they are adjacent to each other. Detailed Note: There is a new page type FIL_PAGE_TYPE_ZLOB_FRAG_ENTRY

and we can call it the fragment pages. Each fragment page contains one or more fragments. Each fragment is represented by a frag_node_t. And each fragment can be of different size. Consider a fragment page containing 4 fragments - f1, f2, f3 and f4. Suppose we free f2 and f3, then we can merge them into one single bigger fragment which is free.
Parameters

[in] next the next fragment.

Returns
true if merge done, false otherwise.

◆ overhead()

static ulint lob::frag_node_t::overhead ( )

inlinestatic

Amount of space that will be used up by meta data.

When a free space is taken from the fragment page to be used as a fragment node, header and footer will be the overhead. Footer is the page dir entry. The page dir entry may not be contiguous with the fragment.

◆ payload()

ulint lob::frag_node_t::payload ( ) const

inline

Get the space available in this fragment for storing data.

◆ print()

std::ostream & lob::frag_node_t::print ( std::ostream & out ) const

inline

◆ ptr()

byte * lob::frag_node_t::ptr ( ) const

inline

Gets the pointer to the beginning of the current fragment.

Note that the beginning of the fragment contains meta data.

Returns: pointer to the beginning of the current fragment.

◆ set_frag_id()

void lob::frag_node_t::set_frag_id ( ulint id )

inline

◆ set_frag_id_null()

void lob::frag_node_t::set_frag_id_null ( )

inline

◆ set_total_len()

void lob::frag_node_t::set_total_len ( ulint len )

inline

Member Data Documentation

◆ m_mtr

mtr_t* lob::frag_node_t::m_mtr

private

The mini-transaction context.

It is only in-memory.

◆ m_node

plist_node_t lob::frag_node_t::m_node

The page list node.

◆ OFFSET_DATA

const ulint lob::frag_node_t::OFFSET_DATA = OFFSET_FRAG_ID + 2

static

The offset where fragment data is stored.

◆ OFFSET_FRAG_ID

const ulint lob::frag_node_t::OFFSET_FRAG_ID = OFFSET_LEN + 2

static

The offset where fragment id is stored.

◆ OFFSET_LEN

const ulint lob::frag_node_t::OFFSET_LEN = plist_node_t::SIZE

static

The offset where the length of fragment is stored.

The length includes both the payload and the meta data overhead.

◆ SIZE_OF_PAGE_DIR_ENTRY

const ulint lob::frag_node_t::SIZE_OF_PAGE_DIR_ENTRY = 2

static

The size of a page directory entry in a fragment page in bytes.

This must be equal to z_frag_page_t::SIZE_OF_PAGE_DIR_ENTRY

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

storage/innobase/include/lob0impl.h

Public Member Functions

Static Public Member Functions

Public Attributes

Static Public Attributes

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ frag_node_t() [1/4]

◆ frag_node_t() [2/4]

◆ frag_node_t() [3/4]

◆ frag_node_t() [4/4]

Member Function Documentation

◆ addr()

◆ data_begin()

◆ decr_length_by_2()

◆ end_ptr()

◆ frag_begin()

◆ frame()

◆ get_frag_id()

◆ get_next_frag()

◆ get_next_node()

◆ get_prev_frag()

◆ get_prev_node()

◆ get_total_len()

◆ header_size()

◆ incr_length_by_2()

◆ is_before()

◆ is_equal() [1/2]

◆ is_equal() [2/2]

◆ is_null()

◆ merge()

◆ overhead()

◆ payload()

◆ print()

◆ ptr()

◆ set_frag_id()

◆ set_frag_id_null()

◆ set_total_len()

Member Data Documentation

◆ m_mtr

◆ m_node

◆ OFFSET_DATA

◆ OFFSET_FRAG_ID

◆ OFFSET_LEN

◆ SIZE_OF_PAGE_DIR_ENTRY