PageSizeUtil (Flink : 2.0-SNAPSHOT API)

java.lang.Object
- org.apache.flink.runtime.io.network.partition.PageSizeUtil

public final class PageSizeUtil
extends Object

Utility for accessing the system page size.

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`CONSERVATIVE_PAGE_SIZE_MULTIPLE`	A conservative fallback value (64 KiBytes) that should be a multiple of the page size even in some uncommon cases of servers installations with larger-than-usual page sizes.
`static int`	`DEFAULT_PAGE_SIZE`	The default page size on most systems.
`static int`	`PAGE_SIZE_UNKNOWN`	Value indicating an unknown page size.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static int`	`getSystemPageSize()`	Tries to get the system page size.
`static int`	`getSystemPageSizeOrConservativeMultiple()`	Tries to get the system page size.
`static int`	`getSystemPageSizeOrDefault()`	Tries to get the system page size.

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

- Field Detail
  - PAGE_SIZE_UNKNOWN
```
public static final int PAGE_SIZE_UNKNOWN
```
    Value indicating an unknown page size.
    
    See Also:
    
    Constant Field Values
  - DEFAULT_PAGE_SIZE
```
public static final int DEFAULT_PAGE_SIZE
```
    The default page size on most systems.
    
    See Also:
    
    Constant Field Values
  - CONSERVATIVE_PAGE_SIZE_MULTIPLE
```
public static final int CONSERVATIVE_PAGE_SIZE_MULTIPLE
```
    A conservative fallback value (64 KiBytes) that should be a multiple of the page size even in some uncommon cases of servers installations with larger-than-usual page sizes.
    
    See Also:
    
    Constant Field Values
- Method Detail
  - getSystemPageSize
```
public static int getSystemPageSize()
```
    Tries to get the system page size. If the page size cannot be determined, this returns -1.
    This internally relies on the presence of "unsafe" and the resolution via some Netty utilities.
  - getSystemPageSizeOrDefault
```
public static int getSystemPageSizeOrDefault()
```
    Tries to get the system page size. If the page size cannot be determined, this returns the DEFAULT_PAGE_SIZE.
  - getSystemPageSizeOrConservativeMultiple
```
public static int getSystemPageSizeOrConservativeMultiple()
```
    Tries to get the system page size. If the page size cannot be determined, this returns the CONSERVATIVE_PAGE_SIZE_MULTIPLE.