org.apache.cassandra.db.compaction
Class SizeTieredCompactionStrategy

java.lang.Object
  org.apache.cassandra.db.compaction.AbstractCompactionStrategy
      org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy

public class SizeTieredCompactionStrategy
extends AbstractCompactionStrategy

Field Summary

protected static long	DEFAULT_MIN_SSTABLE_SIZE
protected int	estimatedRemainingTasks
protected static java.lang.String	MIN_SSTABLE_SIZE_KEY
protected long	minSSTableSize

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

cfs, options

Constructor Summary

SizeTieredCompactionStrategy(ColumnFamilyStore cfs, java.util.Map<java.lang.String,java.lang.String> options)

Method Summary

int	getEstimatedRemainingTasks()
AbstractCompactionTask	getMaximalTask(int gcBefore)
long	getMaxSSTableSize()
long	getMinSSTableSize()
AbstractCompactionTask	getNextBackgroundTask(int gcBefore)
AbstractCompactionTask	getUserDefinedTask(java.util.Collection<SSTableReader> sstables, int gcBefore)
boolean	isKeyExistenceExpensive(java.util.Set<? extends SSTable> sstablesToIgnore)
java.lang.String	toString()

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

getOptions, shutdown

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MIN_SSTABLE_SIZE

protected static final long DEFAULT_MIN_SSTABLE_SIZE

See Also:

Constant Field Values

MIN_SSTABLE_SIZE_KEY

protected static final java.lang.String MIN_SSTABLE_SIZE_KEY

See Also:

Constant Field Values

minSSTableSize

protected long minSSTableSize

estimatedRemainingTasks

protected volatile int estimatedRemainingTasks

Constructor Detail

SizeTieredCompactionStrategy

public SizeTieredCompactionStrategy(ColumnFamilyStore cfs,
                                    java.util.Map<java.lang.String,java.lang.String> options)

Method Detail

getNextBackgroundTask

public AbstractCompactionTask getNextBackgroundTask(int gcBefore)

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.

getMaximalTask

public AbstractCompactionTask getMaximalTask(int gcBefore)

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.

getUserDefinedTask

public AbstractCompactionTask getUserDefinedTask(java.util.Collection<SSTableReader> sstables,
                                                 int gcBefore)

Specified by:

getUserDefinedTask in class AbstractCompactionStrategy

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.)

getEstimatedRemainingTasks

public int getEstimatedRemainingTasks()

Specified by:

getEstimatedRemainingTasks in class AbstractCompactionStrategy

Returns:

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

getMinSSTableSize

public long getMinSSTableSize()

getMaxSSTableSize

public long getMaxSSTableSize()

Specified by:

getMaxSSTableSize in class AbstractCompactionStrategy

Returns:

size in bytes of the largest sstables for this strategy

isKeyExistenceExpensive

public boolean isKeyExistenceExpensive(java.util.Set<? extends SSTable> sstablesToIgnore)

Specified by:

isKeyExistenceExpensive in class AbstractCompactionStrategy

Returns:

true if checking for whether a key exists, ignoring @param sstablesToIgnore, is going to be expensive

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object