buffered_writer< block_type > Class Template Reference

Encapsulates asynchronous buffered block writing engine. More...

#include <buf_writer.h>

Inheritance diagram for buffered_writer< block_type >:

Collaboration diagram for buffered_writer< block_type >:

Public Member Functions
	buffered_writer (unsigned_type write_buf_size, unsigned_type write_batch_size)
	Constructs an object. More...
block_type *	get_free_block ()
	Returns free block from the internal buffer pool. More...
block_type *	write (block_type *filled_block, const bid_type &bid)
	Submits block for writing. More...
void	flush ()
	Flushes not yet written buffers. More...
virtual	~buffered_writer ()
	Flushes not yet written buffers and frees used memory. More...

Protected Types
typedef block_type::bid_type	bid_type
typedef std::priority_queue< batch_entry, std::vector< batch_entry >, batch_entry_cmp >	batch_type

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

Detailed Description

template<typename block_type>
class buffered_writer< block_type >

Encapsulates asynchronous buffered block writing engine.

buffered_writer overlaps I/Os with filling of output buffer.

Constructor & Destructor Documentation

template<typename block_type>

buffered_writer< block_type >::buffered_writer ( unsigned_type  write_buf_size, unsigned_type  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)

template<typename block_type>

virtual buffered_writer< block_type >::~buffered_writer ( )

inlinevirtual

Flushes not yet written buffers and frees used memory.

Member Function Documentation

template<typename block_type>

void buffered_writer< block_type >::flush ( )

inline

Flushes not yet written buffers.

Referenced by stream::runs_creator< from_sorted_sequences< ValueType_ >, Cmp_, BlockSize_, AllocStr_ >::result().

template<typename block_type>

block_type* buffered_writer< block_type >::get_free_block ( )

inline

Returns free block from the internal buffer pool.

Returns

pointer to the block from the internal buffer pool

Referenced by buf_ostream< BlkTp_, BIDIteratorTp_ >::buf_ostream(), and buffered_writer< typed_block >::write().

template<typename block_type>

block_type* buffered_writer< 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

Referenced by stream::runs_creator< from_sorted_sequences< ValueType_ >, Cmp_, BlockSize_, AllocStr_ >::finish(), buf_ostream< BlkTp_, BIDIteratorTp_ >::operator++(), buf_ostream< BlkTp_, BIDIteratorTp_ >::operator<<(), and stream::runs_creator< from_sorted_sequences< ValueType_ >, Cmp_, BlockSize_, AllocStr_ >::push().

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

• buf_writer.h