vrs::RecordManager Class Reference

VRS internal class to manage the records of a specific Recordable after their creation. More...

#include <RecordManager.h>

Public Member Functions
	RecordManager (const RecordManager &)=delete
void	operator= (const RecordManager &)=delete
Record *	createRecord (double timestamp, Record::Type type, uint32_t formatVersion, const DataSource &data)
Record *	createUncompressedRecord (double timestamp, Record::Type type, uint32_t formatVersion, const DataSource &data, std::unique_ptr< DirectWriteRecordData > &&directWriteData)
uint32_t	purgeOldRecords (double oldestTimestamp, bool recycleBuffers=true)
void	purgeCache ()
	Release as much memory as possible, by deleting all the records in the cache.
void	collectOldRecords (double maxAge, list< Record * > &outCollectedRecords)
CompressionPreset	getCompression () const
void	setCompression (CompressionPreset compression)
void	setMaxCacheSize (size_t max)
size_t	getCurrentCacheSize () const

Friends
class	Record

Detailed Description

VRS internal class to manage the records of a specific Recordable after their creation.

Each Recordable has its own RecordManager to minimize (ideally avoid) inter-thread locking. All timestamps are in seconds since some arbitrary point in time, and must be using the same time domain for the entire VRS file.

Member Function Documentation

collectOldRecords()

void vrs::RecordManager::collectOldRecords	(	double	maxAge,
		list< Record * > &	outCollectedRecords
	)

Collect records older than a specific timestamp. The ownership of the records returned is transferred to the caller.

Parameters

maxAge	Max timestamp value of the records to collect.
collectedRecords	A container that will contain the collected records.

createRecord()

Record * vrs::RecordManager::createRecord	(	double	timestamp,
		Record::Type	type,
		uint32_t	formatVersion,
		const DataSource &	data
	)

Create & hold a record using the given parameters. RecordManager is responsible for deleting the record. Copies the data referenced by the DataSource.

Parameters

timestamp	Timestamp of the record, in seconds.
type	Type of the record.
formatVersion	Version number of the format of the record, so that when the record is read, the data can be interpreted appropriately.
data	A DataSource that points to the payload to copy in the record.

Returns

A pointer to the record created.

createUncompressedRecord()

Record * vrs::RecordManager::createUncompressedRecord	(	double	timestamp,
		Record::Type	type,
		uint32_t	formatVersion,
		const DataSource &	data,
		std::unique_ptr< DirectWriteRecordData > &&	directWriteData
	)

Create & hold a record using the given parameters. RecordManager is responsible for deleting the record. Copies the data referenced by the first DataSource, and takes ownership of directWriteData, which will be used to write the last part of the record directly in the file.

Parameters

timestamp	Timestamp of the record, in seconds.
type	Type of the record.
formatVersion	Version number of the format of the record, so that when the record is read, the data can be interpreted appropriately.
data	A DataSource that points to the payload to copy in the record immediately.
directWriteData	data to write directly in the file at the end of the record.

Returns

A pointer to the record created.

getCompression()

CompressionPreset vrs::RecordManager::getCompression ( ) const

inline

Get the compression preset to use when writing the records of this RecordManager.

Returns

The compression preset.

getCurrentCacheSize()

size_t vrs::RecordManager::getCurrentCacheSize ( ) const

inline

Get the count of recycled records are currently waiting to be reused.

Returns

Number of recycled records available.

purgeOldRecords()

uint32_t vrs::RecordManager::purgeOldRecords	(	double	oldestTimestamp,
		bool	recycleBuffers = true
	)

Recycle or delete buffers older than a time.

Parameters

oldestTimestamp	Max timestamp of the records to purge.
recycleBuffers	Tell if old records should be recycled (true) or delete (false).

Returns

Number of records purged.

setCompression()

void vrs::RecordManager::setCompression ( CompressionPreset  compression )

inline

Set the compression preset to use when writing the records of this RecordManager, to override the default value: CompressionPreset::Default.

Parameters

compression

CompressionPreset to use.

setMaxCacheSize()

void vrs::RecordManager::setMaxCacheSize ( size_t  max )

inline

If you know that you have a lot samples that are small. You can increase the cache size to avoid allocations. The default value is kMaxCacheSize = 10.

Parameters

max	The maximum amount of reusable records to keep around.

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

• vrs/RecordManager.h
• vrs/RecordManager.cpp