alluxio.worker.block

Interface BlockWorker

All Superinterfaces:

Server<WorkerNetAddress>, SessionCleanable, Worker

All Known Implementing Classes:

DefaultBlockWorker

public interface BlockWorker
extends Worker, SessionCleanable

A block worker in the Alluxio system.

Method Summary

Modifier and Type	Method and Description
void	abortBlock(long sessionId, long blockId) Aborts the temporary block created by the session.
void	accessBlock(long sessionId, long blockId) Access the block for a given session.
void	closeUfsBlock(long sessionId, long blockId) Closes a UFS block for a client session.
void	commitBlock(long sessionId, long blockId, boolean pinOnCreate) Commits a block to Alluxio managed space.
void	commitBlockInUfs(long blockId, long length) Commits a block in UFS.
String	createBlock(long sessionId, long blockId, String tierAlias, String medium, long initialBytes) Creates a block in Alluxio managed space.
void	createBlockRemote(long sessionId, long blockId, String tierAlias, String medium, long initialBytes) Creates a block.
void	freeSpace(long sessionId, long availableBytes, String tierAlias) Frees space to make a specific amount of bytes available in a best-effort way in the tier.
BlockMeta	getBlockMeta(long sessionId, long blockId, long lockId) Gets the metadata of a specific block from local storage.
BlockStore	getBlockStore()
FileInfo	getFileInfo(long fileId) Gets the file information.
BlockHeartbeatReport	getReport() Gets a report for the periodic heartbeat to master.
BlockStoreMeta	getStoreMeta() Gets the metadata for the entire block store.
BlockStoreMeta	getStoreMetaFull() Similar as getStoreMeta() except that this also contains full blockId list.
BlockWriter	getTempBlockWriterRemote(long sessionId, long blockId) Opens a BlockWriter for an existing temporary block.
BlockMeta	getVolatileBlockMeta(long blockId) Gets the metadata of a block given its blockId or throws IOException.
AtomicReference<Long>	getWorkerId()
boolean	hasBlockMeta(long blockId) Checks if the storage has a given block.
long	lockBlock(long sessionId, long blockId) Obtains a read lock the block.
long	lockBlockNoException(long sessionId, long blockId) Obtains a read lock the block without throwing an exception.
void	moveBlock(long sessionId, long blockId, String tierAlias) Moves a block from its current location to a target location, currently only tier level moves are supported.
void	moveBlockToMedium(long sessionId, long blockId, String mediumType) Moves a block from its current location to a target location, with a specific medium type.
boolean	openUfsBlock(long sessionId, long blockId, Protocol.OpenUfsBlockOptions options) Opens a UFS block.
String	readBlock(long sessionId, long blockId, long lockId) Gets the path to the block file in local storage.
BlockReader	readBlockRemote(long sessionId, long blockId, long lockId) Gets the block reader for the block.
BlockReader	readUfsBlock(long sessionId, long blockId, long offset) Gets a block reader to read a UFS block.
void	removeBlock(long sessionId, long blockId) Frees a block from Alluxio managed space.
void	requestSpace(long sessionId, long blockId, long additionalBytes) Request an amount of space for a block in its storage directory.
void	sessionHeartbeat(long sessionId) Handles the heartbeat from a client.
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.
void	updatePinList(Set<Long> pinnedInodes) Sets the pinlist for the underlying block store.

Methods inherited from interface alluxio.Server

close, getDependencies, getName, getServices, start, stop

Methods inherited from interface alluxio.worker.SessionCleanable

cleanupSession

Method Detail

getBlockStore

BlockStore getBlockStore()

Returns:

the worker data service bind host

getWorkerId

AtomicReference<Long> getWorkerId()

Returns:

the worker id

abortBlock

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

Aborts the temporary block created by the session.

Parameters:

sessionId - the id of the client

blockId - the id of the block to be aborted

Throws:

BlockAlreadyExistsException - if blockId already exists in committed blocks

BlockDoesNotExistException - if the temporary block cannot be found

InvalidWorkerStateException - if blockId does not belong to sessionId

IOException

accessBlock

void accessBlock(long sessionId,
                 long blockId)
          throws BlockDoesNotExistException

Access the block for a given session. This should be called to update the evictor when necessary.

Parameters:

sessionId - the id of the client

blockId - the id of the block to access

Throws:

BlockDoesNotExistException - this exception is not thrown in the tiered block store implementation

commitBlock

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

Commits a block to Alluxio managed space. The block must be temporary. The block is persisted after BlockStore.commitBlock(long, long, boolean). The block will not be accessible until BlockMasterClient.commitBlock(long, long, String, String, long, long) succeeds.

Parameters:

sessionId - the id of the client

blockId - the id of the block to commit

pinOnCreate - whether to pin block on create

Throws:

BlockAlreadyExistsException - if blockId already exists in committed blocks

BlockDoesNotExistException - if the temporary block cannot be found

InvalidWorkerStateException - if blockId does not belong to sessionId

WorkerOutOfSpaceException - if there is no more space left to hold the block

IOException

commitBlockInUfs

void commitBlockInUfs(long blockId,
                      long length)
               throws IOException

Commits a block in UFS.

Parameters:

blockId - the id of the block to commit

length - length of the block to commit

Throws:

IOException

createBlock

String createBlock(long sessionId,
                   long blockId,
                   String tierAlias,
                   String medium,
                   long initialBytes)
            throws BlockAlreadyExistsException,
                   WorkerOutOfSpaceException,
                   IOException

Creates a block in Alluxio managed space. The block will be temporary until it is committed. Throws an IllegalArgumentException if the location does not belong to tiered storage.

Parameters:

sessionId - the id of the client

blockId - the id of the block to create

tierAlias - the alias of the tier to place the new block in, BlockStoreLocation.ANY_TIER for any tier

medium - the name of the medium to place the new block in

initialBytes - the initial amount of bytes to be allocated

Returns:

a string representing the path to the local file

Throws:

BlockAlreadyExistsException - if blockId 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

createBlockRemote

void createBlockRemote(long sessionId,
                       long blockId,
                       String tierAlias,
                       String medium,
                       long initialBytes)
                throws BlockAlreadyExistsException,
                       WorkerOutOfSpaceException,
                       IOException

Creates a block. This method is only called from a data server. Calls getTempBlockWriterRemote(long, long) to get a writer for writing to the block. Throws an IllegalArgumentException if the location does not belong to tiered storage.

Parameters:

sessionId - the id of the client

blockId - the id of the block to be created

tierAlias - the alias of the tier to place the new block in

medium - the name of the medium to place the new block in

initialBytes - the initial amount of bytes to be allocated

Throws:

BlockAlreadyExistsException - if blockId 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

freeSpace

void freeSpace(long sessionId,
               long availableBytes,
               String tierAlias)
        throws WorkerOutOfSpaceException,
               BlockDoesNotExistException,
               IOException,
               BlockAlreadyExistsException,
               InvalidWorkerStateException

Frees space to make a specific amount of bytes available in a best-effort way in the tier. The implementation should try to free at least 1 byte from the worker, otherwise a WorkerOutOfSpaceException should be thrown if no space is available.

Parameters:

sessionId - the session id

availableBytes - the amount of free space in bytes

tierAlias - the alias of the tier to free space

Throws:

WorkerOutOfSpaceException - if there is not enough space

BlockDoesNotExistException - if blocks can not be found

BlockAlreadyExistsException - if blocks to move already exists in destination location

InvalidWorkerStateException - if blocks to move/evict is uncommitted

IOException

getTempBlockWriterRemote

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

Opens a BlockWriter for an existing temporary block. This method is only called from a data server. The temporary block must already exist with #createBlockRemote(long, long, String, long).

Parameters:

sessionId - the id of the client

blockId - the id of the block to be opened for writing

Returns:

the block writer for the local block file

Throws:

BlockDoesNotExistException - if the block cannot be found

BlockAlreadyExistsException - if a committed block with the same ID exists

InvalidWorkerStateException - if the worker state is invalid

IOException

getReport

BlockHeartbeatReport getReport()

Gets a report for the periodic heartbeat to master. Contains the blocks added since the last heart beat and blocks removed since the last heartbeat.

Returns:

a block heartbeat report

getStoreMeta

BlockStoreMeta getStoreMeta()

Gets the metadata for the entire block store. Contains the block mapping per storage dir and the total capacity and used capacity of each tier. This function is cheap.

Returns:

the block store metadata

getStoreMetaFull

BlockStoreMeta getStoreMetaFull()

Similar as getStoreMeta() except that this also contains full blockId list. This function is expensive.

Returns:

the full block store metadata

getVolatileBlockMeta

BlockMeta getVolatileBlockMeta(long blockId)
                        throws BlockDoesNotExistException

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

Parameters:

blockId - the block id

Returns:

metadata of the block

Throws:

BlockDoesNotExistException - if no BlockMeta for this blockId is found

getBlockMeta

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

Gets the metadata of a specific block from local storage.

Unlike getVolatileBlockMeta(long), this method requires the lock id returned by a previously acquired lockBlock(long, long).

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

hasBlockMeta

boolean hasBlockMeta(long blockId)

Checks if the storage has a given block.

Parameters:

blockId - the block id

Returns:

true if the block is contained, false otherwise

lockBlock

long lockBlock(long sessionId,
               long blockId)
        throws BlockDoesNotExistException

Obtains a read lock the block.

Parameters:

sessionId - the id of the client

blockId - the id of the block to be locked

Returns:

the lock id that uniquely identifies the lock obtained

Throws:

BlockDoesNotExistException - if blockId cannot be found, for example, evicted already

lockBlockNoException

long lockBlockNoException(long sessionId,
                          long blockId)

Obtains a read lock the block without throwing an exception. If the lock fails, return BlockLockManager.INVALID_LOCK_ID.

Parameters:

sessionId - the id of the client

blockId - the id of the block to be locked

Returns:

the lock id that uniquely identifies the lock obtained or BlockLockManager.INVALID_LOCK_ID if it failed to lock

moveBlock

void moveBlock(long sessionId,
               long blockId,
               String tierAlias)
        throws BlockDoesNotExistException,
               BlockAlreadyExistsException,
               InvalidWorkerStateException,
               WorkerOutOfSpaceException,
               IOException

Moves a block from its current location to a target location, currently only tier level moves are supported. Throws an IllegalArgumentException if the tierAlias is out of range of tiered storage.

Parameters:

sessionId - the id of the client

blockId - the id of the block to move

tierAlias - the alias of the tier to move the block to

Throws:

BlockDoesNotExistException - if blockId cannot be found

BlockAlreadyExistsException - if blockId already exists in committed blocks of the newLocation

InvalidWorkerStateException - if blockId has not been committed

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

IOException

moveBlockToMedium

void moveBlockToMedium(long sessionId,
                       long blockId,
                       String mediumType)
                throws BlockDoesNotExistException,
                       BlockAlreadyExistsException,
                       InvalidWorkerStateException,
                       WorkerOutOfSpaceException,
                       IOException

Moves a block from its current location to a target location, with a specific medium type. Throws an IllegalArgumentException if the medium type is not one of the listed medium types.

Parameters:

sessionId - the id of the client

blockId - the id of the block to move

mediumType - the medium type to move to

Throws:

BlockDoesNotExistException - if blockId cannot be found

BlockAlreadyExistsException - if blockId already exists in committed blocks of the newLocation

InvalidWorkerStateException - if blockId has not been committed

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

IOException

readBlock

String readBlock(long sessionId,
                 long blockId,
                 long lockId)
          throws BlockDoesNotExistException,
                 InvalidWorkerStateException

Gets the path to the block file in local storage. The block must be a permanent block, and the caller must first obtain the lock on the block.

Parameters:

sessionId - the id of the client

blockId - the id of the block to read

lockId - the id of the lock on this block

Returns:

a string representing the path to this block in local storage

Throws:

BlockDoesNotExistException - if the blockId cannot be found in committed blocks or lockId cannot be found

InvalidWorkerStateException - if sessionId or blockId is not the same as that in the LockRecord of lockId

readBlockRemote

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

Gets the block reader for the block. This method is only called by a data server.

Parameters:

sessionId - the id of the client

blockId - the id of the block to read

lockId - the id of the lock on this block

Returns:

the block reader for the block

Throws:

BlockDoesNotExistException - if lockId is not found

InvalidWorkerStateException - if sessionId or blockId is not the same as that in the LockRecord of lockId

IOException

readUfsBlock

BlockReader readUfsBlock(long sessionId,
                         long blockId,
                         long offset)
                  throws BlockDoesNotExistException,
                         IOException

Gets a block reader to read a UFS block. This method is only called by the data server.

Parameters:

sessionId - the client session ID

blockId - the ID of the UFS block to read

offset - the offset within the block

Returns:

the block reader instance

Throws:

BlockDoesNotExistException - if the block does not exist in the UFS block store

IOException

removeBlock

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

Frees a block from Alluxio managed space.

Parameters:

sessionId - the id of the client

blockId - the id of the block to be freed

Throws:

InvalidWorkerStateException - if blockId has not been committed

BlockDoesNotExistException - if block cannot be found

IOException

requestSpace

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

Request an amount of space for a block in its storage directory. The block must be a temporary block.

Parameters:

sessionId - the id of the client

blockId - the id of the block to allocate space to

additionalBytes - the amount of bytes to allocate

Throws:

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

WorkerOutOfSpaceException - if requested space can not be satisfied

IOException

unlockBlock

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

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:

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

sessionHeartbeat

void sessionHeartbeat(long sessionId)

Handles the heartbeat from a client.

Parameters:

sessionId - the id of the client

updatePinList

void updatePinList(Set<Long> pinnedInodes)

Sets the pinlist for the underlying block store. Typically called by PinListSync.

Parameters:

pinnedInodes - a set of pinned inodes

getFileInfo

FileInfo getFileInfo(long fileId)
              throws IOException

Gets the file information.

Parameters:

fileId - the file id

Returns:

the file info

Throws:

IOException

openUfsBlock

boolean openUfsBlock(long sessionId,
                     long blockId,
                     Protocol.OpenUfsBlockOptions options)
              throws BlockAlreadyExistsException

Opens a UFS block. It registers the block metadata information to the UFS block store. It throws an UfsBlockAccessTokenUnavailableException if the number of concurrent readers on this block exceeds a threshold.

Parameters:

sessionId - the session ID

blockId - the block ID

options - the options

Returns:

whether the UFS block is successfully opened

Throws:

BlockAlreadyExistsException - if the UFS block already exists in the UnderFileSystemBlockStore

closeUfsBlock

void closeUfsBlock(long sessionId,
                   long blockId)
            throws BlockAlreadyExistsException,
                   BlockDoesNotExistException,
                   IOException,
                   WorkerOutOfSpaceException

Closes a UFS block for a client session. It also commits the block to Alluxio block store if the UFS block has been cached successfully.

Parameters:

sessionId - the session ID

blockId - the block ID

Throws:

BlockAlreadyExistsException - if it fails to commit the block to Alluxio block store because the block exists in the Alluxio block store

BlockDoesNotExistException - if the UFS block does not exist in the UnderFileSystemBlockStore

WorkerOutOfSpaceException - the the worker does not have enough space to commit the block

IOException