alluxio.worker.block

Class TieredBlockStore

java.lang.Object

alluxio.worker.block.TieredBlockStore

All Implemented Interfaces:

BlockStore, SessionCleanable, Closeable, AutoCloseable

@NotThreadSafe
public class TieredBlockStore
extends Object
implements BlockStore

This class represents an object store that manages all the blocks in the local tiered storage. This store exposes simple public APIs to operate blocks. Inside this store, it creates an Allocator to decide where to put a new block, an Evictor to decide where to evict a stale block, a BlockMetadataManager to maintain the status of the tiered storage, and a LockManager to coordinate read/write on the same block.

This class is thread-safe, using the following lock hierarchy to ensure thread-safety:

• Any block-level operation (e.g., read, move or remove) on an existing block must acquire a block lock for this block via mLockManager. This block lock is a read/write lock, guarding both the metadata operations and the following I/O on this block. It coordinates different threads (clients) when accessing the same block concurrently.
• Any metadata operation (read or write) must go through mMetaManager and guarded by mMetadataLock. This is also a read/write lock and coordinates different threads (clients) when accessing the shared data structure for metadata.
• Method createBlock(long, long, alluxio.worker.block.AllocateOptions) does not acquire the block lock, because it only creates a temp block which is only visible to its writer before committed (thus no concurrent access).
• Method abortBlock(long, long) does not acquire the block lock, because only temporary blocks can be aborted, and they are only visible to their writers (thus no concurrent access).
• Eviction is done in freeSpaceInternal(long, long, long, alluxio.worker.block.BlockStoreLocation) and it is on the basis of best effort. For operations that may trigger this eviction (e.g., move, create, requestSpace), retry is used

Constructor Summary

Constructors

Constructor and Description
TieredBlockStore() Creates a new instance of TieredBlockStore.

Method Summary

Modifier and Type	Method and Description
void	abortBlock(long sessionId, long blockId) Aborts a temporary block.
void	accessBlock(long sessionId, long blockId) Notifies the block store that a block was accessed so the block store could update accordingly the registered listeners such as evictor and allocator on block access.
boolean	checkStorage() Checks storage health.
void	cleanupSession(long sessionId) Cleans up the data associated with a specific session (typically a dead session).
void	close()
void	commitBlock(long sessionId, long blockId, boolean pinOnCreate) Commits a temporary block to the local store.
long	commitBlockLocked(long sessionId, long blockId, boolean pinOnCreate) Similar to BlockStore.commitBlock(long, long, boolean).
TempBlockMeta	createBlock(long sessionId, long blockId, AllocateOptions options) Creates the metadata of a new block and assigns a temporary path (e.g., a subdir of the final location named after session id) to store its data.
void	freeSpace(long sessionId, long minContiguousBytes, long minAvailableBytes, BlockStoreLocation location) Free space is the entry for immediate block deletion in order to open up space for new or ongoing blocks.
BlockMeta	getBlockMeta(long sessionId, long blockId, long lockId) Gets the metadata of a specific block from local storage.
BlockReader	getBlockReader(long sessionId, long blockId, long lockId) Creates a reader of an existing block to read data from this block.
BlockStoreMeta	getBlockStoreMeta() Gets the metadata of the entire store in a snapshot.
BlockStoreMeta	getBlockStoreMetaFull() Similar as BlockStore.getBlockStoreMeta() except that this includes more information about the block store (e.g.
BlockWriter	getBlockWriter(long sessionId, long blockId) Creates a writer to write data to a temp block.
TempBlockMeta	getTempBlockMeta(long sessionId, long blockId) Gets the temp metadata of a specific block from local storage.
BlockMeta	getVolatileBlockMeta(long blockId) Gets the metadata of a block given its block id or throws BlockDoesNotExistException.
boolean	hasBlockMeta(long blockId) Checks if the storage has a given block.
long	lockBlock(long sessionId, long blockId) Locks an existing block and guards subsequent reads on this block.
long	lockBlockNoException(long sessionId, long blockId) Locks an existing block and guards subsequent reads on this block.
void	moveBlock(long sessionId, long blockId, AllocateOptions moveOptions) Moves an existing block to a new location.
void	moveBlock(long sessionId, long blockId, BlockStoreLocation oldLocation, AllocateOptions moveOptions) Moves an existing block to a new location.
void	registerBlockStoreEventListener(BlockStoreEventListener listener) Registers a BlockStoreEventListener to this block store.
void	removeBlock(long sessionId, long blockId) Removes an existing block.
void	removeBlock(long sessionId, long blockId, BlockStoreLocation location) Removes an existing block.
void	removeDir(StorageDir dir) Removes a storage directory.
void	requestSpace(long sessionId, long blockId, long additionalBytes) Requests to increase the size of a temp block.
void	unlockBlock(long lockId) Releases an acquired block lock based on a lockId (returned by BlockStore.lockBlock(long, long).
boolean	unlockBlock(long sessionId, long blockId) Releases an acquired block lock based on a session id and block id.
void	updatePinnedInodes(Set<Long> inodes) Updates the pinned blocks.

Methods inherited from class java.lang.Object

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

Constructor Detail

TieredBlockStore

public TieredBlockStore()

Creates a new instance of TieredBlockStore.

Method Detail

lockBlock

public long lockBlock(long sessionId,
                      long blockId)
               throws BlockDoesNotExistException

Description copied from interface: BlockStore

Locks an existing block and guards subsequent reads on this block.

Specified by:

lockBlock in interface BlockStore

Parameters:

sessionId - the id of the session to lock this block

blockId - the id of the block to lock

Returns:

the lock id (non-negative) if the lock is acquired successfully

Throws:

BlockDoesNotExistException - if block id can not be found, for example, evicted already

lockBlockNoException

public long lockBlockNoException(long sessionId,
                                 long blockId)

Description copied from interface: BlockStore

Locks an existing block and guards subsequent reads on this block. If the lock fails, return BlockLockManager.INVALID_LOCK_ID.

Specified by:

lockBlockNoException in interface BlockStore

Parameters:

sessionId - the id of the session to lock this block

blockId - the id of the block to lock

Returns:

the lock id (non-negative) that uniquely identifies the lock obtained or BlockLockManager.INVALID_LOCK_ID if it failed to lock

unlockBlock

public void unlockBlock(long lockId)
                 throws BlockDoesNotExistException

Description copied from interface: BlockStore

Releases an acquired block lock based on a lockId (returned by BlockStore.lockBlock(long, long).

Specified by:

unlockBlock in interface BlockStore

Parameters:

lockId - the id of the lock returned by BlockStore.lockBlock(long, long)

Throws:

BlockDoesNotExistException - if lockId can not be found

unlockBlock

public boolean unlockBlock(long sessionId,
                           long blockId)

Description copied from interface: BlockStore

Releases an acquired block lock based on a session id and block id. TODO(calvin): temporary, will be removed after changing client side code.

Specified by:

unlockBlock in interface BlockStore

Parameters:

sessionId - the id of the session to lock this block

blockId - the id of the block to lock

Returns:

false if it fails to unlock due to the lock is not found

getBlockWriter

public BlockWriter getBlockWriter(long sessionId,
                                  long blockId)
                           throws BlockDoesNotExistException,
                                  BlockAlreadyExistsException,
                                  InvalidWorkerStateException,
                                  IOException

Description copied from interface: BlockStore

Creates a writer to write data to a temp block. Since the temp block is "private" to the writer, this operation requires no previously acquired lock.

Specified by:

getBlockWriter in interface BlockStore

Parameters:

sessionId - the id of the session to get the writer

blockId - the id of the temp block

Returns:

a BlockWriter instance on this block

Throws:

BlockDoesNotExistException - if the block can not be found

BlockAlreadyExistsException - if a committed block with the same ID exists

InvalidWorkerStateException - if the worker state is invalid

IOException

getBlockReader

public BlockReader getBlockReader(long sessionId,
                                  long blockId,
                                  long lockId)
                           throws BlockDoesNotExistException,
                                  InvalidWorkerStateException,
                                  IOException

Description copied from interface: BlockStore

Creates a reader of an existing block to read data from this block.

This operation requires the lock id returned by a previously acquired BlockStore.lockBlock(long, long).

Specified by:

getBlockReader in interface BlockStore

Parameters:

sessionId - the id of the session to get the reader

blockId - the id of an existing block

lockId - the id of the lock returned by BlockStore.lockBlock(long, long)

Returns:

a BlockReader instance on this block

Throws:

BlockDoesNotExistException - if lockId is not found

InvalidWorkerStateException - if session id or block id is not the same as that in the LockRecord of lockId

IOException

createBlock

public TempBlockMeta createBlock(long sessionId,
                                 long blockId,
                                 AllocateOptions options)
                          throws BlockAlreadyExistsException,
                                 WorkerOutOfSpaceException,
                                 IOException

Description copied from interface: BlockStore

Creates the metadata of a new block and assigns a temporary path (e.g., a subdir of the final location named after session id) to store its data. The location can be a location with specific tier and dir, or BlockStoreLocation.anyTier(), or BlockStoreLocation.anyDirInTier(String).

Before commit, all the data written to this block will be stored in the temp path and the block is only "visible" to its writer client.

Specified by:

createBlock in interface BlockStore

Parameters:

sessionId - the id of the session

blockId - the id of the block to create

options - allocation options

Returns:

metadata of the temp block created

Throws:

BlockAlreadyExistsException - if block id already exists, either temporary or committed, or block in eviction plan already exists

WorkerOutOfSpaceException - if this Store has no more space than the initialBlockSize

IOException

getVolatileBlockMeta

public BlockMeta getVolatileBlockMeta(long blockId)
                               throws BlockDoesNotExistException

Description copied from interface: BlockStore

Gets the metadata of a block given its block id or throws BlockDoesNotExistException. This method does not require a lock id so the block is possible to be moved or removed after it returns.

Specified by:

getVolatileBlockMeta in interface BlockStore

Parameters:

blockId - the block id

Returns:

metadata of the block

Throws:

BlockDoesNotExistException - if no BlockMeta for this block id is found

getBlockMeta

public BlockMeta getBlockMeta(long sessionId,
                              long blockId,
                              long lockId)
                       throws BlockDoesNotExistException,
                              InvalidWorkerStateException

Description copied from interface: BlockStore

Gets the metadata of a specific block from local storage.

This method requires the lock id returned by a previously acquired BlockStore.lockBlock(long, long).

Specified by:

getBlockMeta in interface BlockStore

Parameters:

sessionId - the id of the session to get this file

blockId - the id of the block

lockId - the id of the lock

Returns:

metadata of the block

Throws:

BlockDoesNotExistException - if the block id can not be found in committed blocks or lockId can not be found

InvalidWorkerStateException - if session id or block id is not the same as that in the LockRecord of lockId

getTempBlockMeta

public TempBlockMeta getTempBlockMeta(long sessionId,
                                      long blockId)

Description copied from interface: BlockStore

Gets the temp metadata of a specific block from local storage.

Specified by:

getTempBlockMeta in interface BlockStore

Parameters:

sessionId - the id of the session to get this file

blockId - the id of the block

Returns:

metadata of the block or null if the temp block does not exist

commitBlock

public void commitBlock(long sessionId,
                        long blockId,
                        boolean pinOnCreate)
                 throws BlockAlreadyExistsException,
                        InvalidWorkerStateException,
                        BlockDoesNotExistException,
                        IOException

Description copied from interface: BlockStore

Commits a temporary block to the local store. After commit, the block will be available in this block store for all clients to access. Since a temp block is "private" to the writer, this method requires no previously acquired lock.

Specified by:

commitBlock in interface BlockStore

Parameters:

sessionId - the id of the session

blockId - the id of a temp block

pinOnCreate - whether to pin block on create

Throws:

BlockAlreadyExistsException - if block id already exists in committed blocks

InvalidWorkerStateException - if block id does not belong to session id

BlockDoesNotExistException - if the temporary block can not be found

IOException

commitBlockLocked

public long commitBlockLocked(long sessionId,
                              long blockId,
                              boolean pinOnCreate)
                       throws BlockAlreadyExistsException,
                              InvalidWorkerStateException,
                              BlockDoesNotExistException,
                              IOException

Description copied from interface: BlockStore

Similar to BlockStore.commitBlock(long, long, boolean). It returns the block locked, so the caller is required to explicitly unlock the block.

Specified by:

commitBlockLocked in interface BlockStore

Parameters:

sessionId - the id of the session

blockId - the id of a temp block

pinOnCreate - whether to pin block on create

Returns:

the lock id

Throws:

BlockAlreadyExistsException - if block id already exists in committed blocks

InvalidWorkerStateException - if block id does not belong to session id

BlockDoesNotExistException - if the temporary block can not be found

IOException

abortBlock

public void abortBlock(long sessionId,
                       long blockId)
                throws BlockAlreadyExistsException,
                       BlockDoesNotExistException,
                       InvalidWorkerStateException,
                       IOException

Description copied from interface: BlockStore

Aborts a temporary block. The metadata of this block will not be added, its data will be deleted and the space will be reclaimed. Since a temp block is "private" to the writer, this requires no previously acquired lock.

Specified by:

abortBlock in interface BlockStore

Parameters:

sessionId - the id of the session

blockId - the id of a temp block

Throws:

BlockAlreadyExistsException - if block id already exists in committed blocks

BlockDoesNotExistException - if the temporary block can not be found

InvalidWorkerStateException - if block id does not belong to session id

IOException

requestSpace

public void requestSpace(long sessionId,
                         long blockId,
                         long additionalBytes)
                  throws BlockDoesNotExistException,
                         WorkerOutOfSpaceException,
                         IOException

Description copied from interface: BlockStore

Requests to increase the size of a temp block. Since a temp block is "private" to the writer client, this operation requires no previously acquired lock.

Specified by:

requestSpace in interface BlockStore

Parameters:

sessionId - the id of the session to request space

blockId - the id of the temp block

additionalBytes - the amount of more space to request in bytes, never be less than 0

Throws:

BlockDoesNotExistException - if block id can not be found, or some block in eviction plan cannot be found

WorkerOutOfSpaceException - if requested space can not be satisfied

IOException

moveBlock

public void moveBlock(long sessionId,
                      long blockId,
                      AllocateOptions moveOptions)
               throws BlockDoesNotExistException,
                      BlockAlreadyExistsException,
                      InvalidWorkerStateException,
                      WorkerOutOfSpaceException,
                      IOException

Description copied from interface: BlockStore

Moves an existing block to a new location.

Specified by:

moveBlock in interface BlockStore

Parameters:

sessionId - the id of the session to move a block

blockId - the id of an existing block

moveOptions - the options for move

Throws:

BlockDoesNotExistException - if block id can not be found

BlockAlreadyExistsException - if block id already exists in committed blocks of the newLocation

InvalidWorkerStateException - if block id has not been committed

WorkerOutOfSpaceException - if newLocation does not have enough extra space to hold the block

IOException

moveBlock

public void moveBlock(long sessionId,
                      long blockId,
                      BlockStoreLocation oldLocation,
                      AllocateOptions moveOptions)
               throws BlockDoesNotExistException,
                      BlockAlreadyExistsException,
                      InvalidWorkerStateException,
                      WorkerOutOfSpaceException,
                      IOException

Description copied from interface: BlockStore

Moves an existing block to a new location.

Specified by:

moveBlock in interface BlockStore

Parameters:

sessionId - the id of the session to remove a block

blockId - the id of an existing block

oldLocation - the location of the source

moveOptions - the options for move

Throws:

BlockDoesNotExistException - if block id can not be found

BlockAlreadyExistsException - if block id already exists in committed blocks of the newLocation

InvalidWorkerStateException - if block id has not been committed

WorkerOutOfSpaceException - if newLocation does not have enough extra space to hold the block

IOException

removeBlock

public void removeBlock(long sessionId,
                        long blockId)
                 throws InvalidWorkerStateException,
                        BlockDoesNotExistException,
                        IOException

Description copied from interface: BlockStore

Removes an existing block. If the block can not be found in this store.

Specified by:

removeBlock in interface BlockStore

Parameters:

sessionId - the id of the session to remove a block

blockId - the id of an existing block

Throws:

InvalidWorkerStateException - if block id has not been committed

BlockDoesNotExistException - if block can not be found

IOException

removeBlock

public void removeBlock(long sessionId,
                        long blockId,
                        BlockStoreLocation location)
                 throws InvalidWorkerStateException,
                        BlockDoesNotExistException,
                        IOException

Description copied from interface: BlockStore

Removes an existing block. If the block can not be found in this store.

Specified by:

removeBlock in interface BlockStore

Parameters:

sessionId - the id of the session to move a block

blockId - the id of an existing block

location - the location of the block

Throws:

InvalidWorkerStateException - if block id has not been committed

BlockDoesNotExistException - if block can not be found

IOException

accessBlock

public void accessBlock(long sessionId,
                        long blockId)
                 throws BlockDoesNotExistException

Description copied from interface: BlockStore

Notifies the block store that a block was accessed so the block store could update accordingly the registered listeners such as evictor and allocator on block access.

Specified by:

accessBlock in interface BlockStore

Parameters:

sessionId - the id of the session to access a block

blockId - the id of an accessed block

Throws:

BlockDoesNotExistException - if the block id is not found

freeSpace

public void freeSpace(long sessionId,
                      long minContiguousBytes,
                      long minAvailableBytes,
                      BlockStoreLocation location)
               throws BlockDoesNotExistException,
                      WorkerOutOfSpaceException,
                      IOException

Free space is the entry for immediate block deletion in order to open up space for new or ongoing blocks. - New blocks creations will not try to free space until all tiers are out of space. - Ongoing blocks could end up freeing space oftenly, when the file's origin location is low on space. This method is synchronized in order to prevent race in its only client, allocations. If not synchronized, new allocations could steal space reserved by ongoing ones. Removing synchronized requires implementing retries to this call along with an optimal locking strategy for fairness. TODO(ggezer): Remove synchronized. TODO(ggezer): Make it a private API.

Specified by:

freeSpace in interface BlockStore

Parameters:

sessionId - the session id

minContiguousBytes - the minimum amount of contigious free space in bytes

minAvailableBytes - the maximum amount of free space in bytes

location - the location to free space

Throws:

BlockDoesNotExistException - if blocks in EvictionPlan can not be found

WorkerOutOfSpaceException - if there is not enough space to fulfill minimum requirement

IOException

cleanupSession

public void cleanupSession(long sessionId)

Description copied from interface: BlockStore

Cleans up the data associated with a specific session (typically a dead session). Clean up entails unlocking the block locks of this session, reclaiming space of temp blocks created by this session, and deleting the session temporary folder.

Specified by:

cleanupSession in interface BlockStore

Specified by:

cleanupSession in interface SessionCleanable

Parameters:

sessionId - the session id

hasBlockMeta

public boolean hasBlockMeta(long blockId)

Description copied from interface: BlockStore

Checks if the storage has a given block.

Specified by:

hasBlockMeta in interface BlockStore

Parameters:

blockId - the block id

Returns:

true if the block is contained, false otherwise

getBlockStoreMeta

public BlockStoreMeta getBlockStoreMeta()

Description copied from interface: BlockStore

Gets the metadata of the entire store in a snapshot. There is no guarantee the state will be consistent with the snapshot after this method is called. This function should be cheap since it is called for every block.

Specified by:

getBlockStoreMeta in interface BlockStore

Returns:

store metadata

getBlockStoreMetaFull

public BlockStoreMeta getBlockStoreMetaFull()

Description copied from interface: BlockStore

Similar as BlockStore.getBlockStoreMeta() except that this includes more information about the block store (e.g. blockId list). This is an expensive operation.

Specified by:

getBlockStoreMetaFull in interface BlockStore

Returns:

full store metadata

registerBlockStoreEventListener

public void registerBlockStoreEventListener(BlockStoreEventListener listener)

Description copied from interface: BlockStore

Registers a BlockStoreEventListener to this block store.

Specified by:

registerBlockStoreEventListener in interface BlockStore

Parameters:

listener - the listener to those events

updatePinnedInodes

public void updatePinnedInodes(Set<Long> inodes)

Updates the pinned blocks.

Specified by:

updatePinnedInodes in interface BlockStore

Parameters:

inodes - a set of ids inodes that are pinned

checkStorage

public boolean checkStorage()

Description copied from interface: BlockStore

Checks storage health.

Specified by:

checkStorage in interface BlockStore

Returns:

true if at least one storage path failed check and is removed, false otherwise

removeDir

public void removeDir(StorageDir dir)

Removes a storage directory.

Parameters:

dir - storage directory to be removed

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException