ClockPageReplacementPolicy (Ignite 2.17.0)

java.lang.Object
- org.apache.ignite.internal.processors.cache.persistence.pagemem.PageReplacementPolicy
- - org.apache.ignite.internal.processors.cache.persistence.pagemem.ClockPageReplacementPolicy

```
public class ClockPageReplacementPolicy
extends PageReplacementPolicy
```
CLOCK page replacement policy implementation.

See Also:

PageReplacementMode.CLOCK

Field Summary
- Fields inherited from class org.apache.ignite.internal.processors.cache.persistence.pagemem.PageReplacementPolicy
  seg

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`ClockPageReplacementPolicy(org.apache.ignite.internal.processors.cache.persistence.pagemem.PageMemoryImpl.Segment seg, long ptr, int pagesCnt)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`onHit(long relPtr)`	Existing page touched.
`void`	`onRemove(long relPtr)`	Page removed from the page memory.
`long`	`replace()`	Finds page to replace.

Methods inherited from class org.apache.ignite.internal.processors.cache.persistence.pagemem.PageReplacementPolicy
onMiss

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ClockPageReplacementPolicy
```
protected ClockPageReplacementPolicy(org.apache.ignite.internal.processors.cache.persistence.pagemem.PageMemoryImpl.Segment seg,
                                     long ptr,
                                     int pagesCnt)
```
    Parameters:
    
    seg - Page memory segment.
    
    ptr - Pointer to memory region.
    
    pagesCnt - Pages count.
- Method Detail
  - onHit
```
public void onHit(long relPtr)
```
    Existing page touched. Note: This method can be invoked under segment write lock or segment read lock.
    
    Overrides:
    
    onHit in class PageReplacementPolicy
  - onRemove
```
public void onRemove(long relPtr)
```
    Page removed from the page memory.
    
    Overrides:
    
    onRemove in class PageReplacementPolicy
  - replace
```
public long replace()
             throws IgniteCheckedException
```
    Finds page to replace. Note: This method always invoked under segment write lock.
    
    Specified by:
    
    replace in class PageReplacementPolicy
    
    Returns:
    
    Relative pointer to page.
    
    Throws:
    
    IgniteCheckedException