Detailed Description

A ByteBlock is the basic storage units of containers like File, BlockQueue, etc.

It consists of a fixed number of bytes without any type and meta information. Conceptually a ByteBlock is written once and can then be shared read-only between containers using CountingPtr<const ByteBlock> reference counting inside a Block, which adds meta information.

ByteBlocks can be swapped to disk, which decreases their size to 0.

Definition at line 51 of file byte_block.hpp.

Inheritance diagram for ByteBlock:

Collaboration diagram for ByteBlock:

#include <byte_block.hpp>

Classes
class	Deleter
	deleter for CountingPtr<ByteBlock> More...

Public Types
using	ByteBlockCPtr = tlx::CountingPtr< const ByteBlock, Deleter >

using	ByteBlockPtr = tlx::CountingPtr< ByteBlock, Deleter >

Public Member Functions
Byte *	begin ()
	mutable data accessor to beginning of memory block More...

const Byte *	begin () const
	const data accessor to beginning of memory block More...

Byte *	data ()
	mutable data accessor to memory block More...

const Byte *	data () const
	const data accessor to memory block More...

void	DecPinCount (size_t local_worker_id)
	decrement pin count, possibly signal block pool that if it reaches zero. More...

Byte *	end ()
	mutable data accessor beyond end of memory block More...

const Byte *	end () const
	const data accessor beyond end of memory block More...

bool	has_ext_file () const
	Returns whether the ByteBlock is in an external file. More...

bool	in_memory () const
	true if block resides in memory More...

void	IncPinCount (size_t local_worker_id)
	increment pin count, must be >= 1 before. More...

bool	is_deleted () const
	true if being deleted More...

size_t	pin_count (size_t local_worker_id) const
	return current pin count More...

std::string	pin_count_str () const
	return string list of pin_counts More...

size_t	size () const
	the block size More...

Public Member Functions inherited from ReferenceCounter
	ReferenceCounter () noexcept
	new objects have zero reference count More...

	ReferenceCounter (const ReferenceCounter &) noexcept
	coping still creates a new object with zero reference count More...

	~ReferenceCounter ()

bool	dec_reference () const noexcept
	Call whenever resetting (i.e. More...

void	inc_reference () const noexcept
	Call whenever setting a pointer to the object. More...

ReferenceCounter &	operator= (const ReferenceCounter &) noexcept
	assignment operator, leaves pointers unchanged More...

size_t	reference_count () const noexcept
	Return the number of references to this object (for debugging) More...

bool	unique () const noexcept
	Test if the ReferenceCounter is referenced by only one CountingPtr. More...

Private Member Functions
	ByteBlock ()=delete
	No default construction of Byteblock. More...

	ByteBlock (BlockPool block_pool, Byte data, size_t size)
	Constructor to initialize ByteBlock in a buffer of memory. More...

	ByteBlock (BlockPool *block_pool, const foxxll::file_ptr &ext_file, int64_t offset, size_t size)

void	OnWriteComplete (foxxll::request *req, bool success)
	forwarded to block_pool_ More...

Private Attributes
BlockPool *	block_pool_
	reference to BlockPool for deletion. More...

Byte *	data_

foxxll::BID< 0 >	em_bid_

foxxll::file_ptr	ext_file_

std::vector< size_t, mem::GPoolAllocator< size_t > >	pin_count_
	counts the number of pins in this block per thread_id. More...

const size_t	size_
	the allocated size of the buffer in bytes More...

size_t	total_pins_ = 0

Static Private Attributes
static constexpr bool	debug = false

Friends
std::ostream &	operator<< (std::ostream &os, const ByteBlock &b)

Member Typedef Documentation

◆ ByteBlockCPtr

using ByteBlockCPtr = tlx::CountingPtr<const ByteBlock, Deleter>

Definition at line 65 of file byte_block.hpp.

◆ ByteBlockPtr

using ByteBlockPtr = tlx::CountingPtr<ByteBlock, Deleter>

Definition at line 64 of file byte_block.hpp.

Constructor & Destructor Documentation

◆ ByteBlock() [1/3]

ByteBlock ( )

privatedelete

No default construction of Byteblock.

◆ ByteBlock() [2/3]

ByteBlock	(	BlockPool *	block_pool,
		Byte *	data,
		size_t	size
	)

private

Constructor to initialize ByteBlock in a buffer of memory.

Protected, used BlockPool::AllocateByteBlock() for construction.

Parameters

data	the memory address of the byte-blocks data. nullptr if swapped out
size	the size of the block in bytes
block_pool	the block pool that manages this ByteBlock

Definition at line 29 of file byte_block.cpp.