Package org.apache.cassandra.io.util

Class MmappedRegions

java.lang.Object

org.apache.cassandra.utils.concurrent.SharedCloseableImpl

org.apache.cassandra.io.util.MmappedRegions

All Implemented Interfaces:

AutoCloseable, SharedCloseable

public class MmappedRegions
extends SharedCloseableImpl

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	MmappedRegions.Region
static final class	MmappedRegions.Tidier

Field Summary

Fields

Modifier and Type	Field	Description
static int	MAX_SEGMENT_SIZE	In a perfect world, MAX_SEGMENT_SIZE would be final, but we need to test with a smaller size

Method Summary

Modifier and Type	Method	Description
void	closeQuietly()
static MmappedRegions	empty(ChannelProxy channel)
boolean	extend(long length, int chunkSize)	Extends this collection of mmapped regions up to the provided total length.
boolean	extend(CompressionMetadata compressionMetadata, int chunkSize)	Extends this collection of mmapped regions up to the length of the compressed file described by the provided metadata.
MmappedRegions.Region	floor(long position)
boolean	isEmpty()
boolean	isValid(ChannelProxy channel)
static MmappedRegions	map(ChannelProxy channel, long length, int chunkSize)
static MmappedRegions	map(ChannelProxy channel, CompressionMetadata metadata)
MmappedRegions	sharedCopy()

Methods inherited from class org.apache.cassandra.utils.concurrent.SharedCloseableImpl

addTo, close, close, isCleanedUp

Methods inherited from class java.lang.Object

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

Field Details

MAX_SEGMENT_SIZE

public static int MAX_SEGMENT_SIZE

In a perfect world, MAX_SEGMENT_SIZE would be final, but we need to test with a smaller size

Method Details

empty

public static MmappedRegions empty(ChannelProxy channel)

map

public static MmappedRegions map(ChannelProxy channel,
 CompressionMetadata metadata)

Parameters:

channel - file to map. the MmappedRegions instance will hold shared copy of given channel.

metadata -

Returns:

new instance

map

public static MmappedRegions map(ChannelProxy channel,
 long length,
 int chunkSize)

sharedCopy

public MmappedRegions sharedCopy()

Returns:

a snapshot of the memory mapped regions. The snapshot can only use existing regions, it cannot create new ones.

extend

public boolean extend(long length,
 int chunkSize)

Extends this collection of mmapped regions up to the provided total length.

Returns:

true if new regions have been created

extend

public boolean extend(CompressionMetadata compressionMetadata,
 int chunkSize)

Extends this collection of mmapped regions up to the length of the compressed file described by the provided metadata.

Returns:

true if new regions have been created

isValid

public boolean isValid(ChannelProxy channel)

isEmpty

public boolean isEmpty()

floor

public MmappedRegions.Region floor(long position)

closeQuietly

public void closeQuietly()