buffered_writer< BlockType > Class Template Reference

Detailed Description

template<typename BlockType>
class foxxll::buffered_writer< BlockType >

Encapsulates asynchronous buffered block writing engine.

buffered_writer overlaps I/Os with filling of output buffer.

Definition at line 37 of file buf_writer.hpp.

Inheritance diagram for buffered_writer< BlockType >:

Collaboration diagram for buffered_writer< BlockType >:

#include <buf_writer.hpp>

Classes
struct	batch_entry
struct	batch_entry_cmp

Public Member Functions
	buffered_writer (size_t write_buf_size, size_t write_batch_size)
	buffered_writer (const buffered_writer &)=delete
	non-copyable: delete copy-constructor More...
	~buffered_writer ()
	Flushes not yet written buffers and frees used memory. More...
void	flush ()
	Flushes not yet written buffers. More...
block_type *	get_free_block ()
buffered_writer &	operator= (const buffered_writer &)=delete
	non-copyable: delete assignment operator More...
block_type *	write (block_type *filled_block, const bid_type &bid)

Protected Types
using	batch_type = std::priority_queue< batch_entry, std::vector< batch_entry >, batch_entry_cmp >

Protected Attributes
batch_type	batch_write_blocks
std::vector< size_t >	busy_write_blocks
std::vector< size_t >	free_write_blocks
const size_t	nwriteblocks
bid_type *	write_bids
block_type *	write_buffers
request_ptr *	write_reqs
const size_t	writebatchsize

Private Types
using	bid_type = typename block_type::bid_type
using	block_type = BlockType

Static Private Attributes
static constexpr bool	debug = false

Member Typedef Documentation

batch_type

using batch_type = std::priority_queue<batch_entry, std::vector<batch_entry>, batch_entry_cmp>

protected

Definition at line 68 of file buf_writer.hpp.

bid_type

using bid_type = typename block_type::bid_type

private

Definition at line 41 of file buf_writer.hpp.

block_type

using block_type = BlockType

private

Definition at line 40 of file buf_writer.hpp.

Constructor & Destructor Documentation

buffered_writer() [1/2]

buffered_writer ( size_t  write_buf_size, size_t  write_batch_size  )

inline

Constructs an object.

Parameters

write_buf_size	number of write buffers to use
write_batch_size	number of blocks to accumulate in order to flush write requests (bulk buffered writing)

Definition at line 76 of file buf_writer.hpp.

Referenced by buffered_writer< block_type >::buffered_writer().

buffered_writer() [2/2]

buffered_writer ( const buffered_writer< BlockType > &  )

delete

non-copyable: delete copy-constructor

~buffered_writer()

~buffered_writer ( )

inline

Flushes not yet written buffers and frees used memory.

Definition at line 194 of file buf_writer.hpp.

Member Function Documentation

flush()

void flush ( )

inline

Flushes not yet written buffers.

Definition at line 164 of file buf_writer.hpp.

get_free_block()

block_type* get_free_block ( )

inline

Returns free block from the internal buffer pool.

Returns

pointer to the block from the internal buffer pool

Definition at line 98 of file buf_writer.hpp.

Referenced by buf_ostream< BlockType, BidIteratorType >::buf_ostream(), and buffered_writer< block_type >::write().

operator=()

buffered_writer& operator= ( const buffered_writer< BlockType > &  )

delete

non-copyable: delete assignment operator

Referenced by buffered_writer< block_type >::buffered_writer().

write()

block_type* write ( block_type *  filled_block, const bid_type &  bid  )

inline

Submits block for writing.

Parameters

filled_block

pointer to the block

Remarks

parameter filled_block must be value returned by get_free_block() or write() methods

Parameters

bid	block identifier, a place to write data of the filled_block

Returns

pointer to the new free block from the pool

Definition at line 137 of file buf_writer.hpp.

Referenced by buf_ostream< BlockType, BidIteratorType >::flush(), buf_ostream< BlockType, BidIteratorType >::operator++(), and buf_ostream< BlockType, BidIteratorType >::operator<<().

Member Data Documentation

batch_write_blocks

batch_type batch_write_blocks

protected

Definition at line 69 of file buf_writer.hpp.

busy_write_blocks

std::vector<size_t> busy_write_blocks

protected

Definition at line 51 of file buf_writer.hpp.

debug

constexpr bool debug = false

staticprivate

Definition at line 39 of file buf_writer.hpp.

free_write_blocks

std::vector<size_t> free_write_blocks

protected

Definition at line 50 of file buf_writer.hpp.

nwriteblocks

const size_t nwriteblocks

protected

Definition at line 44 of file buf_writer.hpp.

Referenced by buffered_writer< block_type >::buffered_writer(), and buffered_writer< block_type >::flush().

write_bids

bid_type* write_bids

protected

Definition at line 46 of file buf_writer.hpp.

Referenced by buffered_writer< block_type >::~buffered_writer().

write_buffers

block_type* write_buffers

protected

Definition at line 45 of file buf_writer.hpp.

Referenced by buffered_writer< block_type >::write(), and buffered_writer< block_type >::~buffered_writer().

write_reqs

request_ptr* write_reqs

protected

Definition at line 47 of file buf_writer.hpp.

Referenced by buffered_writer< block_type >::~buffered_writer().

writebatchsize

const size_t writebatchsize

protected

Definition at line 48 of file buf_writer.hpp.

Referenced by buffered_writer< block_type >::write().

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

• extlib/foxxll/foxxll/mng/buf_writer.hpp