alluxio.client.file.cache

Class DefaultPageMetaStore

java.lang.Object

alluxio.client.file.cache.DefaultPageMetaStore

All Implemented Interfaces:

CacheStatus, PageMetaStore

Direct Known Subclasses:

QuotaPageMetaStore

@NotThreadSafe
public class DefaultPageMetaStore
extends 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 ReentrantReadWriteLock	mLock

Constructor Summary

Constructors

Constructor and Description
DefaultPageMetaStore(List<PageStoreDir> dirs)
DefaultPageMetaStore(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(String fileId, long fileLength)
long	bytes()
void	commitFile(String fileId, String newFileId) Commits a temp file so that all its pages become permanent.
PageInfo	evict(CacheScope scope, PageStoreDir pageStoreDir)
Set<PageInfo>	getAllPagesByFileId(String fileId) Gets all pages by the specified File ID.
ReentrantReadWriteLock	getLock()
PageInfo	getPageInfo(PageId pageId)
PageStoreDir	getStoreDirOfFile(String fileId) Gets the store dir which the specified file is assigned to be cached in.
List<PageStoreDir>	getStoreDirs() Gets the storage directories.
Optional<CacheUsage>	getUsage() Gets cache usage.
boolean	hasPage(PageId pageId)
long	numPages()
PageInfo	removePage(PageId pageId) Removes a page.
PageInfo	removePage(PageId pageId, boolean isTemporary) 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 ReentrantReadWriteLock mLock

Constructor Detail

DefaultPageMetaStore

public DefaultPageMetaStore(List<PageStoreDir> dirs)

Parameters:

dirs - storage directories

DefaultPageMetaStore

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

Constructor of DefaultMetaStore.

Parameters:

dirs - storage directories

allocator - storage allocator

Method Detail

getLock

public 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(String fileId,
                       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

getStoreDirOfFile

public PageStoreDir getStoreDirOfFile(String fileId)
                               throws FileDoesNotExistException

Description copied from interface: PageMetaStore

Gets the store dir which the specified file is assigned to be cached in. Implementations should ensure that all pages of the same file are cached in the same directory, until all the pages of the file are evicted.

Specified by:

getStoreDirOfFile in interface PageMetaStore

Parameters:

fileId - the file ID

Returns:

the store dir which caches the pages of the file

Throws:

FileDoesNotExistException - if the file is not being cached

getStoreDirs

public 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(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,
                           boolean isTemporary)
                    throws PageNotFoundException

Description copied from interface: PageMetaStore

Removes a page.

Specified by:

removePage in interface PageMetaStore

Parameters:

pageId - page identifier

isTemporary - whether is it temporary page or not

Returns:

page info removed

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

getAllPagesByFileId

public Set<PageInfo> getAllPagesByFileId(String fileId)

Description copied from interface: PageMetaStore

Gets all pages by the specified File ID.

Specified by:

getAllPagesByFileId in interface PageMetaStore

Parameters:

fileId - the target file id

Returns:

a set of PageInfo's of this file, otherwise an empty set if not found

getUsage

public Optional<CacheUsage> getUsage()

Description copied from interface: CacheStatus

Gets cache usage.

Specified by:

getUsage in interface CacheStatus

Returns:

cache usage, or none if reporting usage info is not supported