tachyon.worker

Class WorkerClient

java.lang.Object

tachyon.worker.WorkerClient

All Implemented Interfaces:

Closeable, AutoCloseable

public final class WorkerClient
extends Object
implements Closeable

The client talks to a worker server. It keeps sending keep alive message to the worker server. Since WorkerService.Client is not thread safe, this class has to guarantee thread safety.

Constructor Summary

Constructors

Constructor and Description
WorkerClient(NetAddress workerNetAddress, ExecutorService executorService, TachyonConf conf, long sessionId, boolean isLocal, ClientMetrics clientMetrics) Creates a WorkerClient.

Method Summary

Methods

Modifier and Type	Method and Description
void	accessBlock(long blockId) Updates the latest block access time on the worker.
boolean	asyncCheckpoint(long fileId) Notifies the worker to checkpoint the file asynchronously.
void	cacheBlock(long blockId) Notifies the worker the block is cached.
void	cancelBlock(long blockId) Notifies worker that the block has been cancelled
void	close() Closes the connection to worker.
void	createNewSession(long newSessionId) Updates the session id of the client, starting a new session.
InetSocketAddress	getAddress()
InetSocketAddress	getDataServerAddress()
long	getSessionId()
boolean	isConnected()
boolean	isLocal()
String	lockBlock(long blockId) Locks the block, therefore, the worker will not evict the block from the memory until it is unlocked.
void	mustConnect() Connects to the worker.
void	periodicHeartbeat() Called only by WorkerClientHeartbeatExecutor, encapsulates sessionHeartbeat() in order to cancel and cleanup the heartbeating thread in case of failures
void	persistFile(long fileId, long nonce, String path) Notifies the worker that a file has been persisted in a temporary UFS location.
boolean	promoteBlock(long blockId) Promotes block back to the top StorageTier
String	requestBlockLocation(long blockId, long initialBytes) Gets temporary path for the block from the worker
boolean	requestSpace(long blockId, long requestBytes) Requests space for some block from worker
void	sessionHeartbeat() Sends a session heartbeat to the worker.
boolean	unlockBlock(long blockId) Unlocks the block

Methods inherited from class java.lang.Object

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

Constructor Detail

WorkerClient

public WorkerClient(NetAddress workerNetAddress,
            ExecutorService executorService,
            TachyonConf conf,
            long sessionId,
            boolean isLocal,
            ClientMetrics clientMetrics)

Creates a WorkerClient.

Parameters:

workerNetAddress - to worker's location

executorService - the executor service

conf - Tachyon configuration

clientMetrics - metrics of the lcient.

Method Detail

accessBlock

public void accessBlock(long blockId)
                 throws IOException

Updates the latest block access time on the worker.

Parameters:

blockId - The id of the block

Throws:

IOException

persistFile

public void persistFile(long fileId,
               long nonce,
               String path)
                 throws IOException

Notifies the worker that a file has been persisted in a temporary UFS location.

Parameters:

fileId - the file id

nonce - nonce a nonce used for temporary file creation

path - the UFS path where the file should be eventually stored

Throws:

IOException

asyncCheckpoint

public boolean asyncCheckpoint(long fileId)
                        throws IOException

Notifies the worker to checkpoint the file asynchronously.

Parameters:

fileId - The id of the file

Returns:

true if success, false otherwise

Throws:

IOException

cacheBlock

public void cacheBlock(long blockId)
                throws IOException

Notifies the worker the block is cached.

Parameters:

blockId - The id of the block

Throws:

IOException

cancelBlock

public void cancelBlock(long blockId)
                 throws IOException

Notifies worker that the block has been cancelled

Parameters:

blockId - The Id of the block to be cancelled

Throws:

IOException

close

public void close()

Closes the connection to worker. Shutdown the heartbeat thread.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

createNewSession

public void createNewSession(long newSessionId)

Updates the session id of the client, starting a new session. The previous session's held resources should have already been freed, and will be automatically freed after the timeout is exceeded.

Parameters:

newSessionId - the new id that represents the new session

getAddress

public InetSocketAddress getAddress()

Returns:

the address of the worker

getDataServerAddress

public InetSocketAddress getDataServerAddress()

Returns:

the address of the worker's data server

getSessionId

public long getSessionId()

isConnected

public boolean isConnected()

Returns:

true if it's connected to the worker, false otherwise

isLocal

public boolean isLocal()

Returns:

true if the worker is local, false otherwise

lockBlock

public String lockBlock(long blockId)
                 throws IOException

Locks the block, therefore, the worker will not evict the block from the memory until it is unlocked.

Parameters:

blockId - The id of the block

Returns:

the path of the block file locked

Throws:

IOException

mustConnect

public void mustConnect()
                 throws IOException

Connects to the worker.

Throws:

IOException

promoteBlock

public boolean promoteBlock(long blockId)
                     throws IOException

Promotes block back to the top StorageTier

Parameters:

blockId - The id of the block that will be promoted

Returns:

true if succeed, false otherwise

Throws:

IOException

requestBlockLocation

public String requestBlockLocation(long blockId,
                          long initialBytes)
                            throws IOException

Gets temporary path for the block from the worker

Parameters:

blockId - The id of the block

initialBytes - The initial size bytes allocated for the block

Returns:

the temporary path of the block

Throws:

IOException

requestSpace

public boolean requestSpace(long blockId,
                   long requestBytes)
                     throws IOException

Requests space for some block from worker

Parameters:

blockId - The id of the block

requestBytes - The requested space size, in bytes

Returns:

true if success, false otherwise

Throws:

IOException

unlockBlock

public boolean unlockBlock(long blockId)
                    throws IOException

Unlocks the block

Parameters:

blockId - The id of the block

Returns:

true if success, false otherwise

Throws:

IOException

sessionHeartbeat

public void sessionHeartbeat()
                      throws IOException

Sends a session heartbeat to the worker. This renews the client's lease on resources such as locks and temporary files and updates the worker's metrics.

Throws:

IOException - if an error occurs during the heartbeat

periodicHeartbeat

public void periodicHeartbeat()

Called only by WorkerClientHeartbeatExecutor, encapsulates sessionHeartbeat() in order to cancel and cleanup the heartbeating thread in case of failures