org.apache.cassandra.io.util

Interface DiskOptimizationStrategy

All Known Implementing Classes:

SpinningDiskOptimizationStrategy, SsdDiskOptimizationStrategy

public interface DiskOptimizationStrategy

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_BUFFER_SIZE
static int	MIN_BUFFER_SIZE
static int	MIN_BUFFER_SIZE_MASK

Method Summary

Modifier and Type	Method and Description
int	bufferSize(long recordSize)
default int	roundBufferSize(long size) Round up to the next multiple of 4k but no more than MAX_BUFFER_SIZE.
static int	roundForCaching(int size, boolean roundUp) Round either up or down to the next power of two, which is required by the ChunkCache.CachingRebufferer, but capping between MIN_BUFFER_SIZE and MAX_BUFFER_SIZE.

Field Detail

MIN_BUFFER_SIZE

static final int MIN_BUFFER_SIZE

See Also:

Constant Field Values

MIN_BUFFER_SIZE_MASK

static final int MIN_BUFFER_SIZE_MASK

See Also:

Constant Field Values

MAX_BUFFER_SIZE

static final int MAX_BUFFER_SIZE

See Also:

Constant Field Values

Method Detail

bufferSize

int bufferSize(long recordSize)

Parameters:

recordSize - record size

Returns:

the buffer size for a given record size.

roundBufferSize

default int roundBufferSize(long size)

Round up to the next multiple of 4k but no more than MAX_BUFFER_SIZE.

roundForCaching

static int roundForCaching(int size,
                           boolean roundUp)

Round either up or down to the next power of two, which is required by the ChunkCache.CachingRebufferer, but capping between MIN_BUFFER_SIZE and MAX_BUFFER_SIZE.

Parameters:

size - - the size to round to a power of two, normally this is a buffer size that was previously returned by a bufferSize(long).

roundUp - - whether to round up or down

Returns:

a value rounded to a power of two but never bigger than MAX_BUFFER_SIZE or smaller than MIN_BUFFER_SIZE.