geode-docs/developing/partitioned_regions/moving_partitioned_data.html.md.erb

---
title:  Moving Partitioned Region Data to Another Member
---

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You can use the `PartitionRegionHelper` `moveBucketByKey` and `moveData` methods to explicitly move partitioned region data from one member to another.

The `moveBucketByKey` method moves the bucket that contains the specified key from a source member to a destination member. For example, you could use the method to move a popular product item to a new, empty member to reduce load on the source member.

For example:

``` pre
Object product = ...
Region r = ...
DistributedSystem ds = ...
String memberName = ...

//Find the member that is currently hosting the product.
Set<DistributedMember> sourceMembers =
PartitionRegionHelper.getAllMembersForKey(r, product);

//Find the member to move the product to.
DistributedMember destination = ds.findDistributedMember(memberName);

//In this example we assume there is always at least one source.
//In practice, you should check that at least one source
//for the data is available.
source = sourceMembers.iterator().next();

//Move the bucket to the new node. The bucket will
//be moved when this method completes. It throws an exception
//if there is a problem or invalid arguments.
PartitionRegionHelper.moveBucketByKey(r, source, destination, product);
```

See the Java API documentation for `org.apache.geode.cache.partition.PartitionRegionHelper.moveBucketByKey` for more details.

The `moveData` method moves data up to a given percentage (measured in bytes) from a source member to a destination member. For example, you could use this method to move a specified percentage of data from an overloaded member to another member to improve distribution.

For example:

``` pre
Region r = ...
DistributedSystem ds = ...
String sourceName = ...
String destName = ...

//Find the source member.
DistributedMember source = ds.findDistributedMember(sourceName);
DistributedMember destination = ds.findDistributedMember(destName);

//Move up to 20% of the data from the source to the destination node.
PartitionRegionHelper.moveData(r, source, destination, 20);
```

See the Java API documentation for `org.apache.geode.cache.partition.PartitionRegionHelper.moveData` for more details.

For more information on partitioned regions and rebalancing, see [Partitioned Regions](chapter_overview.html).