Package com.linkedin.davinci.store.memory

Class InMemoryStoragePartition

java.lang.Object

com.linkedin.davinci.store.AbstractStoragePartition

com.linkedin.davinci.store.memory.InMemoryStoragePartition

public class InMemoryStoragePartition
extends AbstractStoragePartition

An in-memory hashmap implementation of a storage partition Assumptions: 1.No need to worry about synchronizing write/deletes as the model is based on a single writer. So all updates are already serialized. 2. Concurrent reads may be stale if writes/deletes are going on. But the consistency model is also designed to be eventual. Since "read your own writes semantics" is not guaranteed this eventual consistency is tolerable. Even though there will be one writer and 1 or more readers, we may still need a concurrentHashMap to avoid ConcurrentModicfictionException thrown from the iterators

Field Summary

Fields inherited from class com.linkedin.davinci.store.AbstractStoragePartition

partitionId

Constructor Summary

Constructors

Constructor	Description
InMemoryStoragePartition(Integer partitionId)

Method Summary

Modifier and Type	Method	Description
void	cleanupSnapshot()	Cleans up the snapshot
void	close()	Close the specific partition
void	createSnapshot()	Creates a snapshot of the current state of the storage if the blob transfer feature is enabled via the store configuration
void	delete(byte[] key)	Delete a key from the partition database
void	drop()	Drop when it is not required anymore.
byte[]	get(byte[] key)	Get a value from the partition database
byte[]	get(ByteBuffer key)
<K, V> V	get(K key)	Get a Value from the partition database
void	getByKeyPrefix(byte[] keyPrefix, BytesStreamingCallback callback)	Populate provided callback with key-value pairs from the partition database where the keys have provided prefix.
long	getPartitionSizeInBytes()	Get the partition database size in bytes
void	put(byte[] key, byte[] value)	Puts a value into the partition database
void	put(byte[] key, ByteBuffer valueBuffer)
<K, V> void	put(K key, V value)
Map<String,String>	sync()	Sync current database.
boolean	verifyConfig(StoragePartitionConfig storagePartitionConfig)	Check whether current storage partition verifyConfig the given partition config

Methods inherited from class com.linkedin.davinci.store.AbstractStoragePartition

beginBatchWrite, checkDatabaseIntegrity, deleteWithReplicationMetadata, endBatchWrite, get, getIterator, getPartitionId, getReplicationMetadata, getRmdByteUsage, putReplicationMetadata, putWithReplicationMetadata, putWithReplicationMetadata, reopen, validateBatchIngestion

Methods inherited from class java.lang.Object

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

Constructor Details

InMemoryStoragePartition

public InMemoryStoragePartition(Integer partitionId)

Method Details

put

public void put(byte[] key,
 byte[] value)

Description copied from class: AbstractStoragePartition

Puts a value into the partition database

Specified by:

put in class AbstractStoragePartition

put

public void put(byte[] key,
 ByteBuffer valueBuffer)

Specified by:

put in class AbstractStoragePartition

put

public <K,
V> void put(K key,
 V value)

Specified by:

put in class AbstractStoragePartition

get

public byte[] get(byte[] key)
           throws PersistenceFailureException

Description copied from class: AbstractStoragePartition

Get a value from the partition database

Specified by:

get in class AbstractStoragePartition

Parameters:

key - key to be retrieved

Returns:

null if the key does not exist, byte[] value if it exists.

Throws:

PersistenceFailureException

get

public <K,
V> V get(K key)

Description copied from class: AbstractStoragePartition

Get a Value from the partition database

Specified by:

get in class AbstractStoragePartition

Type Parameters:

K - the type for Key

V - the type for the return value

Parameters:

key - key to be retrieved

Returns:

null if the key does not exist, V value if it exists

get

public byte[] get(ByteBuffer key)

Specified by:

get in class AbstractStoragePartition

getByKeyPrefix

public void getByKeyPrefix(byte[] keyPrefix,
 BytesStreamingCallback callback)

Description copied from class: AbstractStoragePartition

Populate provided callback with key-value pairs from the partition database where the keys have provided prefix. If prefix is null, callback will be populated will all key-value pairs from the partition database.

Specified by:

getByKeyPrefix in class AbstractStoragePartition

delete

public void delete(byte[] key)

Description copied from class: AbstractStoragePartition

Delete a key from the partition database

Specified by:

delete in class AbstractStoragePartition

sync

public Map<String,String> sync()

Description copied from class: AbstractStoragePartition

Sync current database.

Specified by:

sync in class AbstractStoragePartition

Returns:

Database related info, which is required to be checkpointed.

drop

public void drop()

Description copied from class: AbstractStoragePartition

Drop when it is not required anymore.

Specified by:

drop in class AbstractStoragePartition

close

public void close()

Description copied from class: AbstractStoragePartition

Close the specific partition

Specified by:

close in class AbstractStoragePartition

verifyConfig

public boolean verifyConfig(StoragePartitionConfig storagePartitionConfig)

Description copied from class: AbstractStoragePartition

Check whether current storage partition verifyConfig the given partition config

Specified by:

verifyConfig in class AbstractStoragePartition

Returns:

getPartitionSizeInBytes

public long getPartitionSizeInBytes()

Description copied from class: AbstractStoragePartition

Get the partition database size in bytes

Specified by:

getPartitionSizeInBytes in class AbstractStoragePartition

Returns:

partition database size

createSnapshot

public void createSnapshot()

Description copied from class: AbstractStoragePartition

Creates a snapshot of the current state of the storage if the blob transfer feature is enabled via the store configuration

Specified by:

createSnapshot in class AbstractStoragePartition

cleanupSnapshot

public void cleanupSnapshot()

Description copied from class: AbstractStoragePartition

Cleans up the snapshot

Specified by:

cleanupSnapshot in class AbstractStoragePartition