alluxio.worker.block

Class BlockLockManager

java.lang.Object

alluxio.worker.block.BlockLockManager

@ThreadSafe
public final class BlockLockManager
extends Object

Handle all block locks.

Constructor Summary

Constructors

Constructor and Description
BlockLockManager() Constructs a new BlockLockManager.

Method Summary

Modifier and Type	Method and Description
void	cleanupSession(long sessionId) Cleans up the locks currently hold by a specific session.
Set<Long>	getLockedBlocks() Gets a set of currently locked blocks.
long	lockBlock(long sessionId, long blockId, BlockLockType blockLockType) Locks a block.
long	tryLockBlock(long sessionId, long blockId, BlockLockType blockLockType, long time, TimeUnit unit) Tries to lock a block within the given time.
void	unlockBlock(long lockId) Releases the lock with the specified lock id.
boolean	unlockBlock(long sessionId, long blockId) Releases the lock with the specified session and block id.
boolean	unlockBlockNoException(long lockId) Releases the lock with the specified lock id.
void	validate() Checks the internal state of the manager to make sure invariants hold.
void	validateLock(long sessionId, long blockId, long lockId) Validates the lock is hold by the given session for the given block.

Methods inherited from class java.lang.Object

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

Constructor Detail

BlockLockManager

public BlockLockManager()

Constructs a new BlockLockManager.

Method Detail

lockBlock

public long lockBlock(long sessionId,
                      long blockId,
                      BlockLockType blockLockType)

Locks a block. Note that even if this block does not exist, a lock id is still returned. If all PropertyKey.WORKER_TIERED_STORE_BLOCK_LOCKS are already in use and no lock has been allocated for the specified block, this method will need to wait until a lock can be acquired from the lock pool.

Parameters:

sessionId - the session id

blockId - the block id

blockLockType - BlockLockType.READ or BlockLockType.WRITE

Returns:

lock id

tryLockBlock

public long tryLockBlock(long sessionId,
                         long blockId,
                         BlockLockType blockLockType,
                         long time,
                         TimeUnit unit)

Tries to lock a block within the given time. Note that even if this block does not exist, a lock id is still returned. If all PropertyKey.WORKER_TIERED_STORE_BLOCK_LOCKS are already in use and no lock has been allocated for the specified block, this method will need to wait until a lock can be acquired from the lock pool.

Parameters:

sessionId - the session id

blockId - the block id

blockLockType - BlockLockType.READ or BlockLockType.WRITE

time - the maximum time to wait for the lock

unit - the time unit of the time argument

Returns:

lock id or INVALID_LOCK_ID if not able to lock within the given time

unlockBlockNoException

public boolean unlockBlockNoException(long lockId)

Releases the lock with the specified lock id.

Parameters:

lockId - the id of the lock to release

Returns:

whether the lock corresponding the lock ID has been successfully unlocked

unlockBlock

public void unlockBlock(long lockId)
                 throws BlockDoesNotExistException

Releases the lock with the specified lock id.

Parameters:

lockId - the id of the lock to release

Throws:

BlockDoesNotExistException - if lock id cannot be found

unlockBlock

public boolean unlockBlock(long sessionId,
                           long blockId)

Releases the lock with the specified session and block id.

Parameters:

sessionId - the session id

blockId - the block id

Returns:

whether the block has been successfully unlocked

validateLock

public void validateLock(long sessionId,
                         long blockId,
                         long lockId)
                  throws BlockDoesNotExistException,
                         InvalidWorkerStateException

Validates the lock is hold by the given session for the given block.

Parameters:

sessionId - the session id

blockId - the block id

lockId - the lock id

Throws:

BlockDoesNotExistException - when no lock record can be found for lock id

InvalidWorkerStateException - when session id or block id is not consistent with that in the lock record for lock id

cleanupSession

public void cleanupSession(long sessionId)

Cleans up the locks currently hold by a specific session.

Parameters:

sessionId - the id of the session to cleanup

getLockedBlocks

public Set<Long> getLockedBlocks()

Gets a set of currently locked blocks.

Returns:

a set of locked blocks

validate

public void validate()

Checks the internal state of the manager to make sure invariants hold. This method is intended for testing purposes. A runtime exception will be thrown if invalid state is encountered.