com.tangosol.net.cache
Interface CacheStatistics

All Known Implementing Classes:

PartitionSplittingBackingMap.AggregatingCacheStatistics, SimpleCacheStatistics

public interface CacheStatistics

An interface for exposing Cache statistics.

Since:

Coherence 2.2

Author:

cp 2003.05.26

Method Summary

double	getAverageGetMillis() Determine the average number of milliseconds per get() invocation since the cache statistics were last reset.
double	getAverageHitMillis() Determine the average number of milliseconds per get() invocation that is a hit.
double	getAverageMissMillis() Determine the average number of milliseconds per get() invocation that is a miss.
double	getAveragePutMillis() Determine the average number of milliseconds per put() invocation since the cache statistics were last reset.
long	getCacheHits() Determine the rough number of cache hits since the cache statistics were last reset.
long	getCacheHitsMillis() Determine the total number of milliseconds (since that last statistics reset) for the get() operations for which an entry existed in this map.
long	getCacheMisses() Determine the rough number of cache misses since the cache statistics were last reset.
long	getCacheMissesMillis() Determine the total number of milliseconds (since that last statistics reset) for the get() operations for which no entry existed in this map.
long	getCachePrunes() Determine the rough number of cache pruning cycles since the cache statistics were last reset.
long	getCachePrunesMillis() Determine the total number of milliseconds (since that last statistics reset) spent on cache pruning.
double	getHitProbability() Determine the rough probability (0 <= p <= 1) that the next invocation will be a hit, based on the statistics collected since the last reset of the cache statistics.
long	getTotalGets() Determine the total number of get() operations since the cache statistics were last reset.
long	getTotalGetsMillis() Determine the total number of milliseconds spent on get() operations since the cache statistics were last reset.
long	getTotalPuts() Determine the total number of put() operations since the cache statistics were last reset.
long	getTotalPutsMillis() Determine the total number of milliseconds spent on put() operations since the cache statistics were last reset.
void	resetHitStatistics() Reset all of the cache statistics.

Method Detail

getTotalGets

long getTotalGets()

Determine the total number of get() operations since the cache statistics were last reset.

Returns:

the total number of get() operations

getTotalGetsMillis

long getTotalGetsMillis()

Determine the total number of milliseconds spent on get() operations since the cache statistics were last reset.

Returns:

the total number of milliseconds processing get() operations

getAverageGetMillis

double getAverageGetMillis()

Determine the average number of milliseconds per get() invocation since the cache statistics were last reset.

Returns:

the average number of milliseconds per get() operation

getTotalPuts

long getTotalPuts()

Determine the total number of put() operations since the cache statistics were last reset.

Returns:

the total number of put() operations

getTotalPutsMillis

long getTotalPutsMillis()

Determine the total number of milliseconds spent on put() operations since the cache statistics were last reset.

Returns:

the total number of milliseconds processing put() operations

getAveragePutMillis

double getAveragePutMillis()

Determine the average number of milliseconds per put() invocation since the cache statistics were last reset.

Returns:

the average number of milliseconds per put() operation

getCacheHits

long getCacheHits()

Determine the rough number of cache hits since the cache statistics were last reset.

A cache hit is a read operation invocation (e.g. get()) for which an entry exists in this map.

Returns:

the number of get() calls that have been served by existing cache entries

getCacheHitsMillis

long getCacheHitsMillis()

Determine the total number of milliseconds (since that last statistics reset) for the get() operations for which an entry existed in this map.

Returns:

the total number of milliseconds for the get() operations that were hits

getAverageHitMillis

double getAverageHitMillis()

Determine the average number of milliseconds per get() invocation that is a hit.

Returns:

the average number of milliseconds per cache hit

getCacheMisses

long getCacheMisses()

Determine the rough number of cache misses since the cache statistics were last reset.

A cache miss is a get() invocation that does not have an entry in this map.

Returns:

the number of get() calls that failed to find an existing cache entry because the requested key was not in the cache

getCacheMissesMillis

long getCacheMissesMillis()

Determine the total number of milliseconds (since that last statistics reset) for the get() operations for which no entry existed in this map.

Returns:

the total number of milliseconds (since that last statistics reset) for the get() operations that were misses

getAverageMissMillis

double getAverageMissMillis()

Determine the average number of milliseconds per get() invocation that is a miss.

Returns:

the average number of milliseconds per cache miss

getHitProbability

double getHitProbability()

Determine the rough probability (0 <= p <= 1) that the next invocation will be a hit, based on the statistics collected since the last reset of the cache statistics.

Returns:

the cache hit probability (0 <= p <= 1)

getCachePrunes

long getCachePrunes()

Determine the rough number of cache pruning cycles since the cache statistics were last reset.

For the LocalCache implementation, this refers to the number of times that the prune() method is executed.

Returns:

the total number of cache pruning cycles (since that last statistics reset)

getCachePrunesMillis

long getCachePrunesMillis()

Determine the total number of milliseconds (since that last statistics reset) spent on cache pruning.

For the LocalCache implementation, this refers to the time spent in the prune() method.

Returns:

the total number of milliseconds (since that last statistics reset) for cache pruning operations

resetHitStatistics

void resetHitStatistics()

Reset all of the cache statistics.

Note that the method name implies that only the hit statistics are cleared, which is not the case; all of the statistics are cleared.