com.continuent.tungsten.replicator.storage.parallel
Class ShardListPartitioner

java.lang.Object
  com.continuent.tungsten.replicator.storage.parallel.ShardListPartitioner

All Implemented Interfaces:

Partitioner

public class ShardListPartitioner
extends java.lang.Object
implements Partitioner

Partitions events using a map that directs shard assignment to partition numbers. The default shard map location is by convention tungsten-replicator/conf/shard.list. The shard map structure follows the example shown here.

 # Shard map file. 
 # Explicit database name match. 
 common1=0
 common2=0
 db1=1
 db2=2
 db3=3
 
 # Default partition for shards that do not match explicit name. 
 # Permissible values are either a partition number or -1 in 
 # which case values are hashed across available partitions. 
 (*)=4
 
 # Comma-separated list of shards that require critical section to run. 
 (critical)=common1,common2
 
 # Method for channel hash assignments.  Allowed values are round-robin and 
 # string-hash. 
 (hash-method)=string-hash
 

Version:

1.0

Author:

Robert Hodges

Constructor Summary

ShardListPartitioner()
Create new instance of partitioner.

Method Summary

PartitionerResponse	partition(ReplDBMSHeader event, int taskId) Assign an event to a particular partition.
void	setContext(PluginContext context) Assigns the current runtime context in case the partitioner needs to refer to replicator state.
void	setPartitions(int availablePartitions) Sets the number of available partitions.
void	setShardMap(java.io.File shardMap)

Methods inherited from class java.lang.Object

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

Constructor Detail

ShardListPartitioner

public ShardListPartitioner()

Create new instance of partitioner.

Method Detail

setShardMap

public void setShardMap(java.io.File shardMap)

setPartitions

public void setPartitions(int availablePartitions)

Sets the number of available partitions.

Specified by:

setPartitions in interface Partitioner

Parameters:

availablePartitions - Number of partitions available

See Also:

Partitioner.setPartitions(int)

setContext

public void setContext(PluginContext context)

Assigns the current runtime context in case the partitioner needs to refer to replicator state.

Specified by:

setContext in interface Partitioner

Parameters:

context - Replicator runtime context

See Also:

Partitioner.setContext(com.continuent.tungsten.replicator.plugin.PluginContext)

partition

public PartitionerResponse partition(ReplDBMSHeader event,
                                     int taskId)
                              throws ReplicatorException

Assign an event to a particular partition. All fragments of a particular sequence number must go to the same partition.

Specified by:

partition in interface Partitioner

Parameters:

event - Event to be assigned a partition

taskId - Task id of input thread

Returns:

Response containing partition ID and whether event requires a critical section

Throws:

ReplicatorException

See Also:

Partitioner.partition(com.continuent.tungsten.replicator.event.ReplDBMSHeader, int)