Package org.apache.hadoop.fs.impl.prefetch

Class EmptyPrefetchingStatistics

java.lang.Object

org.apache.hadoop.fs.impl.prefetch.EmptyPrefetchingStatistics

All Implemented Interfaces:

PrefetchingStatistics, IOStatisticsSource

public final class EmptyPrefetchingStatistics
extends java.lang.Object
implements PrefetchingStatistics

Empty implementation of the prefetching statistics interface.

Method Summary

Modifier and Type	Method	Description
void	blockAddedToFileCache()	A block has been saved to the file cache.
void	blockEvictedFromFileCache()	A block has been evicted from the file cache.
void	blockRemovedFromFileCache()	A block has been removed from the file cache.
void	executorAcquired(java.time.Duration timeInQueue)	An executor has been acquired, either for prefetching or caching.
static EmptyPrefetchingStatistics	getInstance()
void	memoryAllocated(int size)	A new buffer has been added to the buffer pool.
void	memoryFreed(int size)	Previously allocated memory has been freed.
void	prefetchOperationCompleted()	A prefetch operation has completed.
DurationTracker	prefetchOperationStarted()	A prefetch operation has started.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.fs.statistics.IOStatisticsSource

getIOStatistics

Method Detail

getInstance

public static EmptyPrefetchingStatistics getInstance()

prefetchOperationStarted

public DurationTracker prefetchOperationStarted()

Description copied from interface: PrefetchingStatistics

A prefetch operation has started.

Specified by:

prefetchOperationStarted in interface PrefetchingStatistics

Returns:

duration tracker

blockAddedToFileCache

public void blockAddedToFileCache()

Description copied from interface: PrefetchingStatistics

A block has been saved to the file cache.

Specified by:

blockAddedToFileCache in interface PrefetchingStatistics

blockRemovedFromFileCache

public void blockRemovedFromFileCache()

Description copied from interface: PrefetchingStatistics

A block has been removed from the file cache.

Specified by:

blockRemovedFromFileCache in interface PrefetchingStatistics

blockEvictedFromFileCache

public void blockEvictedFromFileCache()

Description copied from interface: PrefetchingStatistics

A block has been evicted from the file cache.

Specified by:

blockEvictedFromFileCache in interface PrefetchingStatistics

prefetchOperationCompleted

public void prefetchOperationCompleted()

Description copied from interface: PrefetchingStatistics

A prefetch operation has completed.

Specified by:

prefetchOperationCompleted in interface PrefetchingStatistics

executorAcquired

public void executorAcquired(java.time.Duration timeInQueue)

Description copied from interface: PrefetchingStatistics

An executor has been acquired, either for prefetching or caching.

Specified by:

executorAcquired in interface PrefetchingStatistics

Parameters:

timeInQueue - time taken to acquire an executor.

memoryAllocated

public void memoryAllocated(int size)

Description copied from interface: PrefetchingStatistics

A new buffer has been added to the buffer pool.

Specified by:

memoryAllocated in interface PrefetchingStatistics

Parameters:

size - size of the new buffer

memoryFreed

public void memoryFreed(int size)

Description copied from interface: PrefetchingStatistics

Previously allocated memory has been freed.

Specified by:

memoryFreed in interface PrefetchingStatistics

Parameters:

size - size of memory freed.