LogConsumer Class Reference

Provides a record-at-a-time interface to the recovery log using asynchronous read operations. More...

#include <log_consumer.h>

Public Member Functions
	LogConsumer (lsn_t startLSN, size_t blockSize, bool ignore=true)
virtual	~LogConsumer ()
void	shutdown ()
void	open (lsn_t endLSN, bool readWholeBlocks=false)
bool	next (logrec_t *&lr)
lsn_t	getNextLSN ()

Static Public Member Functions
static void	initLogScanner (LogScanner *logScanner)

Private Member Functions
bool	nextBlock ()

Private Attributes
AsyncRingBuffer *	readbuf
ReaderThread *	reader
LogScanner *	logScanner
lsn_t	nextLSN
lsn_t	endLSN
char *	currentBlock
size_t	blockSize
size_t	pos
bool	readWholeBlocks

Detailed Description

Provides a record-at-a-time interface to the recovery log using asynchronous read operations.

This class manages an asynchronous reader thread (see ReaderThread) and the corresponding read buffer (see AsyncRingBuffer). It provides a record-at-a-time synchronous interface to the caller. It is used to read log records from the recovery log and push them into the archiver heap.

Access requires a preliminary call to the open() method, which activates the reader thread with the given end LSN. Otherwise, the next() method bay block indefinitely.

next() returns false when it reaches the end LSN, implying that the returned log record is invalid.

Author

Caetano Sauer

Constructor & Destructor Documentation

LogConsumer()

LogConsumer::LogConsumer	(	lsn_t	startLSN,
		size_t	blockSize,
		bool	ignore = true
	)

~LogConsumer()

LogConsumer::~LogConsumer ( )

virtual

Member Function Documentation

getNextLSN()

lsn_t LogConsumer::getNextLSN ( )

inline

initLogScanner()

void LogConsumer::initLogScanner ( LogScanner *  logScanner )

static

next()

bool LogConsumer::next

(

logrec_t *&

lr

)

nextBlock()

bool LogConsumer::nextBlock ( )

private

open()

void LogConsumer::open	(	lsn_t	endLSN,
		bool	readWholeBlocks = false
	)

shutdown()

void LogConsumer::shutdown

(

)

Member Data Documentation

blockSize

size_t LogConsumer::blockSize

private

currentBlock

char* LogConsumer::currentBlock

private

endLSN

lsn_t LogConsumer::endLSN

private

logScanner

LogScanner* LogConsumer::logScanner

private

nextLSN

lsn_t LogConsumer::nextLSN

private

pos

size_t LogConsumer::pos

private

readbuf

AsyncRingBuffer* LogConsumer::readbuf

private

reader

ReaderThread* LogConsumer::reader

private

readWholeBlocks

bool LogConsumer::readWholeBlocks

private

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

• src/sm/log_consumer.h
• src/sm/log_consumer.cpp