com.neeve.rog.log

Class RogLogCompactor

java.lang.Object

com.neeve.root.RootObject

com.neeve.rog.RogObject

com.neeve.rog.log.RogLogCompactor

public final class RogLogCompactor
extends RogObject

Compacts a log's live log file

Threading:

A log compactor is not safe for concurrent access by multiple threads.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RogLogCompactor.Params Contains parameters for compaction.
static class	RogLogCompactor.State Enmerates the various compactor states

Method Summary

Methods

Modifier and Type	Method and Description
RogLogCompactor	compact() Perform the log compaction This method kicks off the background compaction of the live transaction log file.
RogLogCompactor	compact(long forceCheckpointCompletionOn) Perform the log compaction
long	getMaxCompactionWindowSize() Gets the compaction window size in Bytes.
double	getMaxCompactionWindowSize(UtlUnit.ByteUnit unit) Gets the compaction window size.
long	getNewLogInitialLogSize() Gets the size of new log files creted by the compactor.
RogLogCompactor.State	getState() Get the current compaction state
boolean	isCompactionInProgress() Get is compaction is in progress
void	setMaxCompactionWindowSize(double size, UtlUnit.ByteUnit byteUnit) May be used to change the compaction windows size.
void	setMaxCompactionWindowSize(long size) May be used to change the compaction windows size.
void	setNewLogInitialLogSize(long initialLogSize) Sets the intial size (in bytes) for the log into which entries will be written.
void	stop() Stop any running compaction
void	waitForCompactionToComplete() Wait for compaction to complete

Methods inherited from class com.neeve.root.RootObject

getChecked, getThreaded, getTracer, setChecked, setTracer

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

setMaxCompactionWindowSize

public final void setMaxCompactionWindowSize(double size,
                              UtlUnit.ByteUnit byteUnit)

May be used to change the compaction windows size.

Parameters:

size - The size (in megabytes) to set for the compaction window.

byteUnit - The byte unit to use.

Throws:

IllegalStateException - if isCompactionInProgress() is true.

IllegalArgumentException - if the compaction window size is invalid (<=0).

getMaxCompactionWindowSize

public final double getMaxCompactionWindowSize(UtlUnit.ByteUnit unit)

Gets the compaction window size.

Parameters:

unit - The byte unit in which to return the compaction window size.

Returns:

The current compaction window size in the given target unit.

setMaxCompactionWindowSize

public final void setMaxCompactionWindowSize(long size)

May be used to change the compaction windows size.

Parameters:

size - The size (in megabytes) to set for the compaction window.

Throws:

IllegalStateException - if isCompactionInProgress() is true.

IllegalArgumentException - if the compaction window size is invalid (<=0).

getMaxCompactionWindowSize

public final long getMaxCompactionWindowSize()

Gets the compaction window size in Bytes.

Returns:

The current compaction window size in bytes.

setNewLogInitialLogSize

public void setNewLogInitialLogSize(long initialLogSize)

Sets the intial size (in bytes) for the log into which entries will be written.

Parameters:

initialLogSize - The initial log size of the compacted log or -1 to use the initial log size configured for the source log.

getNewLogInitialLogSize

public long getNewLogInitialLogSize()

Gets the size of new log files creted by the compactor.

Returns:

The new log initial log size.

getState

public final RogLogCompactor.State getState()

Get the current compaction state

compact

public final RogLogCompactor compact(long forceCheckpointCompletionOn)

Perform the log compaction

Parameters:

forceCheckpointCompletionOn - Specifies a checkpoint version that forces the completion of a checkpoint in the compacted log. This value is used in conjunction with the compaction window to determine when to complete a checkpoint in the compacted log. A value of <=0 in this parameter will cause only the compaction window to be used. A value of > 0 will cause the compaction window to be used but will force the checkpoint to be completed immediately after processing the checkpoint version specified in this parameter.

This method kicks off the background compaction of the live transaction log file. The caller can track the status of the compaction by polling the state via the getState() method.

compact

public final RogLogCompactor compact()

Perform the log compaction

This method kicks off the background compaction of the live transaction log file. The caller can track the status of the compaction by polling the state via the getState() method.

isCompactionInProgress

public final boolean isCompactionInProgress()

Get is compaction is in progress

waitForCompactionToComplete

public final void waitForCompactionToComplete()
                                       throws Exception

Wait for compaction to complete

Throws:

Exception

stop

public final void stop()

Stop any running compaction