alluxio.client.file.cache

Class DefaultPageMetaStore

java.lang.Object

alluxio.client.file.cache.DefaultPageMetaStore

All Implemented Interfaces:

PageMetaStore

Direct Known Subclasses:

QuotaPageMetaStore

@NotThreadSafe
public class DefaultPageMetaStore
extends java.lang.Object
implements PageMetaStore

The default implementation of a metadata store for pages stored in cache. This implementation is not thread safe and requires synchronizations on external callers by acquiring the associated lock.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.concurrent.locks.ReentrantReadWriteLock	mLock

Constructor Summary

Constructors

Constructor and Description
DefaultPageMetaStore(java.util.List<PageStoreDir> dirs)
DefaultPageMetaStore(java.util.List<PageStoreDir> dirs, Allocator allocator) Constructor of DefaultMetaStore.

Method Summary

Modifier and Type	Method and Description
void	addPage(PageId pageId, PageInfo pageInfo) Adds a new page to the cache.
void	addTempPage(PageId pageId, PageInfo pageInfo) Adds a new temp page to the cache.
PageStoreDir	allocate(java.lang.String fileId, long fileLength)
long	bytes()
void	commitFile(java.lang.String fileId, java.lang.String newFileId) Commits a temp file so that all its pages become permanent.
PageInfo	evict(CacheScope scope, PageStoreDir pageStoreDir)
java.util.concurrent.locks.ReentrantReadWriteLock	getLock()
PageInfo	getPageInfo(PageId pageId)
java.util.List<PageStoreDir>	getStoreDirs() Gets the storage directories.
boolean	hasPage(PageId pageId)
long	numPages()
PageInfo	removePage(PageId pageId) Removes a page.
void	reset() Resets the meta store.

Methods inherited from class java.lang.Object

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

Methods inherited from interface alluxio.client.file.cache.PageMetaStore

create, evict

Field Detail

mLock

protected final java.util.concurrent.locks.ReentrantReadWriteLock mLock

Constructor Detail

DefaultPageMetaStore

public DefaultPageMetaStore(java.util.List<PageStoreDir> dirs)

Parameters:

dirs - storage directories

DefaultPageMetaStore

public DefaultPageMetaStore(java.util.List<PageStoreDir> dirs,
                            Allocator allocator)

Constructor of DefaultMetaStore.

Parameters:

dirs - storage directories

allocator - storage allocator

Method Detail

getLock

public java.util.concurrent.locks.ReentrantReadWriteLock getLock()

Specified by:

getLock in interface PageMetaStore

Returns:

the associated lock

hasPage

public boolean hasPage(PageId pageId)

Specified by:

hasPage in interface PageMetaStore

Parameters:

pageId - page identifier

Returns:

if a page is stored in cache

addPage

public void addPage(PageId pageId,
                    PageInfo pageInfo)

Description copied from interface: PageMetaStore

Adds a new page to the cache.

Specified by:

addPage in interface PageMetaStore

Parameters:

pageId - page identifier

pageInfo - info of the page

addTempPage

public void addTempPage(PageId pageId,
                        PageInfo pageInfo)

Description copied from interface: PageMetaStore

Adds a new temp page to the cache.

Specified by:

addTempPage in interface PageMetaStore

Parameters:

pageId - page identifier

pageInfo - info of the page

commitFile

public void commitFile(java.lang.String fileId,
                       java.lang.String newFileId)
                throws PageNotFoundException

Description copied from interface: PageMetaStore

Commits a temp file so that all its pages become permanent.

Specified by:

commitFile in interface PageMetaStore

Parameters:

fileId - the temp file to commit

newFileId - the new file name of the file after committing

Throws:

PageNotFoundException

getStoreDirs

public java.util.List<PageStoreDir> getStoreDirs()

Description copied from interface: PageMetaStore

Gets the storage directories.

Specified by:

getStoreDirs in interface PageMetaStore

Returns:

the storage directories

allocate

public PageStoreDir allocate(java.lang.String fileId,
                             long fileLength)

Specified by:

allocate in interface PageMetaStore

Returns:

the storage directory

getPageInfo

public PageInfo getPageInfo(PageId pageId)
                     throws PageNotFoundException

Specified by:

getPageInfo in interface PageMetaStore

Parameters:

pageId - page identifier

Returns:

page info

Throws:

PageNotFoundException

removePage

public PageInfo removePage(PageId pageId)
                    throws PageNotFoundException

Description copied from interface: PageMetaStore

Removes a page.

Specified by:

removePage in interface PageMetaStore

Parameters:

pageId - page identifier

Returns:

page info removed

Throws:

PageNotFoundException

bytes

public long bytes()

Specified by:

bytes in interface PageMetaStore

Returns:

the total size of pages stored in bytes

numPages

public long numPages()

Specified by:

numPages in interface PageMetaStore

Returns:

the number of pages stored

reset

public void reset()

Description copied from interface: PageMetaStore

Resets the meta store.

Specified by:

reset in interface PageMetaStore

evict

@Nullable
public PageInfo evict(CacheScope scope,
                                PageStoreDir pageStoreDir)

Specified by:

evict in interface PageMetaStore

Returns:

a page to evict