S4LruPolicy (simulator 3.1.5 API)

java.lang.Object
- com.github.benmanes.caffeine.cache.simulator.policy.linked.S4LruPolicy

All Implemented Interfaces:

Policy, Policy.KeyOnlyPolicy
```
public final class S4LruPolicy
extends Object
implements Policy.KeyOnlyPolicy
```
"Quadruply-segmented LRU. Four queues are maintained at levels 0 to 3. On a cache miss, the item is inserted at the head of queue 0. On a cache hit, the item is moved to the head of the next higher queue (items in queue 3 move to the head of queue 3). Each queue is allocated 1/4 of the total cache size and items are evicted from the tail of a queue to the head of the next lower queue to maintain the size invariants. Items evicted from queue 0 are evicted from the cache." For more details, see An Analysis of Facebook Photo Caching.

Nested Class Summary
- Nested classes/interfaces inherited from interface com.github.benmanes.caffeine.cache.simulator.policy.Policy
  Policy.Characteristic, Policy.KeyOnlyPolicy, Policy.PolicySpec

Constructor Summary

Constructors
Constructor Description

S4LruPolicy(Admission admission, Config config)

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`finished()`	Indicates that the recording has completed.
`static Set<Policy>`	`policies(Config config)`	Returns all variations of this policy based on the configuration parameters.
`void`	`record(long key)`
`PolicyStats`	`stats()`	Returns the cache efficiency statistics.

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.policy.Policy
name

Methods inherited from interface com.github.benmanes.caffeine.cache.simulator.policy.Policy.KeyOnlyPolicy
record

- Constructor Detail
  - S4LruPolicy
```
public S4LruPolicy(Admission admission,
                   Config config)
```
- Method Detail
  - policies
```
public static Set<Policy> policies(Config config)
```
    Returns all variations of this policy based on the configuration parameters.
  - record
```
public void record(long key)
```
    Specified by:
    
    record in interface Policy.KeyOnlyPolicy
  - finished
```
public void finished()
```
    Description copied from interface: Policy
    
    Indicates that the recording has completed.
    
    Specified by:
    
    finished in interface Policy
  - stats
```
public PolicyStats stats()
```
    Description copied from interface: Policy
    
    Returns the cache efficiency statistics.
    
    Specified by:
    
    stats in interface Policy