org.apache.hadoop.hbase.master.normalizer

Interface RegionNormalizer

All Known Implementing Classes:

SimpleRegionNormalizer

@InterfaceAudience.Private
public interface RegionNormalizer

Performs "normalization" of regions on the cluster, making sure that suboptimal choice of split keys doesn't leave cluster in a situation when some regions are substantially larger than others for considerable amount of time. Users who want to use this feature could either use default SimpleRegionNormalizer or plug in their own implementation. Please note that overly aggressive normalization rules (attempting to make all regions perfectly equal in size) could potentially lead to "split/merge storms".

Method Summary

Modifier and Type	Method and Description
List<NormalizationPlan>	computePlanForTable(TableName table) Computes next optimal normalization plan.
long	getSkippedCount(NormalizationPlan.PlanType type)
void	planSkipped(RegionInfo hri, NormalizationPlan.PlanType type) Notification for the case where plan couldn't be executed due to constraint violation, such as namespace quota
void	setMasterRpcServices(MasterRpcServices masterRpcServices) Set the master RPC service.
void	setMasterServices(MasterServices masterServices) Set the master service.

Method Detail

setMasterServices

void setMasterServices(MasterServices masterServices)

Set the master service. Must be called before first call to computePlanForTable(TableName).

Parameters:

masterServices - master services to use

setMasterRpcServices

void setMasterRpcServices(MasterRpcServices masterRpcServices)

Set the master RPC service. Must be called before first call to computePlanForTable(TableName).

Parameters:

masterRpcServices - master RPC services to use

computePlanForTable

List<NormalizationPlan> computePlanForTable(TableName table)
                                     throws HBaseIOException

Computes next optimal normalization plan.

Parameters:

table - table to normalize

Returns:

normalization actions to perform. Null if no action to take

Throws:

HBaseIOException

planSkipped

void planSkipped(RegionInfo hri,
                 NormalizationPlan.PlanType type)

Notification for the case where plan couldn't be executed due to constraint violation, such as namespace quota

Parameters:

hri - the region which is involved in the plan

type - type of plan

getSkippedCount

long getSkippedCount(NormalizationPlan.PlanType type)

Parameters:

type - type of plan for which skipped count is to be returned

Returns:

the count of plans of specified type which were skipped