com.github.benmanes.caffeine.cache.simulator.admission.countmin4

Class PeriodicResetCountMin4

java.lang.Object

com.github.benmanes.caffeine.cache.simulator.admission.countmin4.CountMin4

com.github.benmanes.caffeine.cache.simulator.admission.countmin4.PeriodicResetCountMin4

All Implemented Interfaces:

Frequency

public final class PeriodicResetCountMin4
extends CountMin4

A sketch where the aging process is a periodic reset.

Field Summary

Fields inherited from class com.github.benmanes.caffeine.cache.simulator.admission.countmin4.CountMin4

conservative, step, table, tableMask

Constructor Summary

Constructors

Constructor and Description
PeriodicResetCountMin4(Config config)

Method Summary

Modifier and Type	Method and Description
protected void	ensureCapacity(long maximumSize) Increases the capacity of this FrequencySketch instance, if necessary, to ensure that it can accurately estimate the popularity of elements given the maximum size of the cache.
int	frequency(long e) Returns the estimated number of occurrences of an element, up to the maximum (15).
void	increment(long e) Increments the popularity of the element if it does not exceed the maximum (15).
protected void	tryReset(boolean added) Reduces every counter by half of its original value.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.github.benmanes.caffeine.cache.simulator.admission.Frequency

reportMiss

Constructor Detail

PeriodicResetCountMin4

public PeriodicResetCountMin4(Config config)

Method Detail

ensureCapacity

protected void ensureCapacity(long maximumSize)

Description copied from class: CountMin4

Increases the capacity of this FrequencySketch instance, if necessary, to ensure that it can accurately estimate the popularity of elements given the maximum size of the cache. This operation forgets all previous counts when resizing.

Overrides:

ensureCapacity in class CountMin4

Parameters:

maximumSize - the maximum size of the cache

frequency

public int frequency(long e)

Description copied from class: CountMin4

Returns the estimated number of occurrences of an element, up to the maximum (15).

Specified by:

frequency in interface Frequency

Overrides:

frequency in class CountMin4

Parameters:

e - the element to count occurrences of

Returns:

the estimated number of occurrences of the element; possibly zero but never negative

increment

public void increment(long e)

Description copied from class: CountMin4

Increments the popularity of the element if it does not exceed the maximum (15). The popularity of all elements will be periodically down sampled when the observed events exceeds a threshold. This process provides a frequency aging to allow expired long term entries to fade away.

Specified by:

increment in interface Frequency

Overrides:

increment in class CountMin4

Parameters:

e - the element to add

tryReset

protected void tryReset(boolean added)

Reduces every counter by half of its original value. To reduce the truncation error, the sample is reduced by the number of counters with an odd value.

Overrides:

tryReset in class CountMin4