Package org.apache.cassandra.db.compaction

Class LeveledCompactionStrategy

java.lang.Object

org.apache.cassandra.db.compaction.AbstractCompactionStrategy

org.apache.cassandra.db.compaction.LeveledCompactionStrategy

public class LeveledCompactionStrategy
extends AbstractCompactionStrategy

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.cassandra.db.compaction.AbstractCompactionStrategy

AbstractCompactionStrategy.ScannerList

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_LEVEL_FANOUT_SIZE

Fields inherited from class org.apache.cassandra.db.compaction.AbstractCompactionStrategy

cfs, COMPACTION_ENABLED, DEFAULT_LOG_ALL_OPTION, DEFAULT_TOMBSTONE_COMPACTION_INTERVAL, DEFAULT_TOMBSTONE_THRESHOLD, DEFAULT_UNCHECKED_TOMBSTONE_COMPACTION_OPTION, disableTombstoneCompactions, isActive, LOG_ALL_OPTION, logAll, ONLY_PURGE_REPAIRED_TOMBSTONES, options, TOMBSTONE_COMPACTION_INTERVAL_OPTION, TOMBSTONE_THRESHOLD_OPTION, tombstoneCompactionInterval, tombstoneThreshold, UNCHECKED_TOMBSTONE_COMPACTION_OPTION, uncheckedTombstoneCompaction

Constructor Summary

Constructors

Constructor	Description
LeveledCompactionStrategy(ColumnFamilyStore cfs, Map<String,String> options)

Method Summary

Modifier and Type	Method	Description
void	addSSTable(SSTableReader added)	Adds sstable, note that implementations must handle duplicate notifications here (added already being in the compaction strategy)
void	addSSTables(Iterable<SSTableReader> sstables)	Adds sstables, note that implementations must handle duplicate notifications here (added already being in the compaction strategy)
int[]	getAllLevelSize()
long[]	getAllLevelSizeBytes()
AbstractCompactionTask	getCompactionTask(LifecycleTransaction txn, long gcBefore, long maxSSTableBytes)
int	getEstimatedRemainingTasks()
int	getLevelFanoutSize()
int	getLevelSize(int i)
Collection<AbstractCompactionTask>	getMaximalTask(long gcBefore, boolean splitOutput)
long	getMaxSSTableBytes()
AbstractCompactionTask	getNextBackgroundTask(long gcBefore)	the only difference between background and maximal in LCS is that maximal is still allowed (by explicit user request) even when compaction is disabled.
AbstractCompactionStrategy.ScannerList	getScanners(Collection<SSTableReader> sstables, Collection<Range<Token>> ranges)	Returns a list of KeyScanners given sstables and a range on which to scan.
protected Set<SSTableReader>	getSSTables()	Returns the sstables managed by this strategy instance
AbstractCompactionTask	getUserDefinedTask(Collection<SSTableReader> sstables, long gcBefore)
Collection<Collection<SSTableReader>>	groupSSTablesForAntiCompaction(Collection<SSTableReader> ssTablesToGroup)	Leveled compaction strategy has guarantees on the data contained within each level so we have to make sure we only create groups of SSTables with members from the same level.
void	metadataChanged(StatsMetadata oldMetadata, SSTableReader sstable)	Called when the metadata has changed for an sstable - for example if the level changed Not called when repair status changes (which is also metadata), because this results in the sstable getting removed from the compaction strategy instance.
void	removeSSTable(SSTableReader sstable)	Removes sstable from the strategy, implementations must be able to handle the sstable having already been removed.
void	replaceSSTables(Collection<SSTableReader> removed, Collection<SSTableReader> added)	Replaces sstables in the compaction strategy Note that implementations must be able to handle duplicate notifications here (that removed are already gone and added have already been added)
void	startup()	Performs any extra initialization required
CompactionLogger.Strategy	strategyLogger()
String	toString()
static Map<String,String>	validateOptions(Map<String,String> options)

Methods inherited from class org.apache.cassandra.db.compaction.AbstractCompactionStrategy

createSSTableMultiWriter, filterSuspectSSTables, getDirectories, getName, getScanners, getScanners, pause, removeSSTables, resume, shutdown, supportsEarlyOpen, worthDroppingTombstones

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

DEFAULT_LEVEL_FANOUT_SIZE

public static final int DEFAULT_LEVEL_FANOUT_SIZE

See Also:

• Constant Field Values

Constructor Details

LeveledCompactionStrategy

public LeveledCompactionStrategy(ColumnFamilyStore cfs,
 Map<String,String> options)

Method Details

getLevelSize

public int getLevelSize(int i)

getAllLevelSize

public int[] getAllLevelSize()

getAllLevelSizeBytes

public long[] getAllLevelSizeBytes()

startup

public void startup()

Description copied from class: AbstractCompactionStrategy

Performs any extra initialization required

Overrides:

startup in class AbstractCompactionStrategy

getNextBackgroundTask

public AbstractCompactionTask getNextBackgroundTask(long gcBefore)

the only difference between background and maximal in LCS is that maximal is still allowed (by explicit user request) even when compaction is disabled.

Specified by:

getNextBackgroundTask in class AbstractCompactionStrategy

Parameters:

gcBefore - throw away tombstones older than this

Returns:

the next background/minor compaction task to run; null if nothing to do. Is responsible for marking its sstables as compaction-pending.

getMaximalTask

public Collection<AbstractCompactionTask> getMaximalTask(long gcBefore,
 boolean splitOutput)

Specified by:

getMaximalTask in class AbstractCompactionStrategy

Parameters:

gcBefore - throw away tombstones older than this

Returns:

a compaction task that should be run to compact this columnfamilystore as much as possible. Null if nothing to do. Is responsible for marking its sstables as compaction-pending.

getUserDefinedTask

public AbstractCompactionTask getUserDefinedTask(Collection<SSTableReader> sstables,
 long gcBefore)

Specified by:

getUserDefinedTask in class AbstractCompactionStrategy

Parameters:

sstables - SSTables to compact. Must be marked as compacting.

gcBefore - throw away tombstones older than this

Returns:

a compaction task corresponding to the requested sstables. Will not be null. (Will throw if user requests an invalid compaction.) Is responsible for marking its sstables as compaction-pending.

getCompactionTask

public AbstractCompactionTask getCompactionTask(LifecycleTransaction txn,
 long gcBefore,
 long maxSSTableBytes)

Overrides:

getCompactionTask in class AbstractCompactionStrategy

groupSSTablesForAntiCompaction

public Collection<Collection<SSTableReader>> groupSSTablesForAntiCompaction(Collection<SSTableReader> ssTablesToGroup)

Leveled compaction strategy has guarantees on the data contained within each level so we have to make sure we only create groups of SSTables with members from the same level. This way we won't end up creating invalid sstables during anti-compaction.

Overrides:

groupSSTablesForAntiCompaction in class AbstractCompactionStrategy

Parameters:

ssTablesToGroup -

Returns:

Groups of sstables from the same level

getEstimatedRemainingTasks

public int getEstimatedRemainingTasks()

Specified by:

getEstimatedRemainingTasks in class AbstractCompactionStrategy

Returns:

the number of background tasks estimated to still be needed for this columnfamilystore

getMaxSSTableBytes

public long getMaxSSTableBytes()

Specified by:

getMaxSSTableBytes in class AbstractCompactionStrategy

Returns:

size in bytes of the largest sstables for this strategy

getLevelFanoutSize

public int getLevelFanoutSize()

getScanners

public AbstractCompactionStrategy.ScannerList getScanners(Collection<SSTableReader> sstables,
 Collection<Range<Token>> ranges)

Description copied from class: AbstractCompactionStrategy

Returns a list of KeyScanners given sstables and a range on which to scan. The default implementation simply grab one SSTableScanner per-sstable, but overriding this method allow for a more memory efficient solution if we know the sstable don't overlap (see LeveledCompactionStrategy for instance).

Overrides:

getScanners in class AbstractCompactionStrategy

replaceSSTables

public void replaceSSTables(Collection<SSTableReader> removed,
 Collection<SSTableReader> added)

Description copied from class: AbstractCompactionStrategy

Replaces sstables in the compaction strategy Note that implementations must be able to handle duplicate notifications here (that removed are already gone and added have already been added)

Overrides:

replaceSSTables in class AbstractCompactionStrategy

metadataChanged

public void metadataChanged(StatsMetadata oldMetadata,
 SSTableReader sstable)

Description copied from class: AbstractCompactionStrategy

Called when the metadata has changed for an sstable - for example if the level changed Not called when repair status changes (which is also metadata), because this results in the sstable getting removed from the compaction strategy instance.

Overrides:

metadataChanged in class AbstractCompactionStrategy

addSSTables

public void addSSTables(Iterable<SSTableReader> sstables)

Description copied from class: AbstractCompactionStrategy

Adds sstables, note that implementations must handle duplicate notifications here (added already being in the compaction strategy)

Overrides:

addSSTables in class AbstractCompactionStrategy

addSSTable

public void addSSTable(SSTableReader added)

Description copied from class: AbstractCompactionStrategy

Adds sstable, note that implementations must handle duplicate notifications here (added already being in the compaction strategy)

Specified by:

addSSTable in class AbstractCompactionStrategy

removeSSTable

public void removeSSTable(SSTableReader sstable)

Description copied from class: AbstractCompactionStrategy

Removes sstable from the strategy, implementations must be able to handle the sstable having already been removed.

Specified by:

removeSSTable in class AbstractCompactionStrategy

getSSTables

protected Set<SSTableReader> getSSTables()

Description copied from class: AbstractCompactionStrategy

Returns the sstables managed by this strategy instance

Specified by:

getSSTables in class AbstractCompactionStrategy

toString

public String toString()

Overrides:

toString in class Object

strategyLogger

public CompactionLogger.Strategy strategyLogger()

Overrides:

strategyLogger in class AbstractCompactionStrategy

validateOptions

public static Map<String,String> validateOptions(Map<String,String> options)
                                          throws ConfigurationException

Throws:

ConfigurationException