Package org.apache.cassandra.repair.autorepair

Class RepairTokenRangeSplitter

java.lang.Object

org.apache.cassandra.repair.autorepair.RepairTokenRangeSplitter

All Implemented Interfaces:

IAutoRepairTokenRangeSplitter

public class RepairTokenRangeSplitter
extends Object
implements IAutoRepairTokenRangeSplitter

The default implementation of IAutoRepairTokenRangeSplitter that attempts to:

1. Create smaller, consistent repair times
2. Minimize the impact on hosts
3. Reduce overstreaming
4. Reduce number of repairs

To achieve these goals, this implementation inspects SSTable metadata to estimate the bytes and number of partitions within a range and splits it accordingly to bound the size of the token ranges used for repair assignments.

Refer to Auto Repair documentation for this implementation for a more thorough breakdown of this implementation.

While this splitter has a lot of tuning parameters, the expectation is that the established default configuration shall be sensible for all AutoRepairConfig.RepairType's. The following configuration parameters are offered.

Configuration parameters:

• bytes_per_assignment – Target size (in compressed bytes) for each repair. Throttles incremental repair and anticompaction per schedule after incremental repairs are enabled.
• max_bytes_per_schedule – Maximum data (in compressed bytes) to cover in a single schedule. Acts as a throttle for the repair cycle workload. Tune this up if writes are outpacing repair, or down if repairs are too disruptive. Alternatively, adjust min_repair_interval.
• partitions_per_assignment – Maximum number of partitions per repair assignment. Limits the number of partitions in Merkle tree leaves to prevent overstreaming.
• max_tables_per_assignment – Maximum number of tables to include in a single repair assignment. Especially useful for keyspaces with many tables. Prevents excessive batching of tables that exceed other parameters like bytes_per_assignment or partitions_per_assignment.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	RepairTokenRangeSplitter.RepairTypeDefaults	Conveinence builder for establishing defaults by repair type.
protected static class	RepairTokenRangeSplitter.SizedRepairAssignment	Implementation of RepairAssignment that also assigns an estimation of bytes involved in the repair.

Constructor Summary

Constructors

Constructor	Description
RepairTokenRangeSplitter(AutoRepairConfig.RepairType repairType, Map<String,String> parameters)

Method Summary

Modifier and Type	Method	Description
protected static long	getEstimatedBytes(List<RepairTokenRangeSplitter.SizedRepairAssignment> repairAssignments)
Map<String,String>	getParameters()
Iterator<KeyspaceRepairAssignments>	getRepairAssignments(boolean primaryRangeOnly, List<PrioritizedRepairPlan> repairPlans)	Split the token range you wish to repair into multiple assignments.
protected List<RepairTokenRangeSplitter.SizedRepairAssignment>	getRepairAssignments(AutoRepairUtils.SizeEstimate estimate)
protected List<RepairTokenRangeSplitter.SizedRepairAssignment>	getRepairAssignmentsForTable(KeyspaceRepairPlan repairPlan, String tableName, Range<Token> tokenRange)
void	setParameter(String key, String value)	Update a configuration parameter.

Methods inherited from class java.lang.Object

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

Constructor Details

RepairTokenRangeSplitter

public RepairTokenRangeSplitter(AutoRepairConfig.RepairType repairType,
 Map<String,String> parameters)

Method Details

getRepairAssignments

public Iterator<KeyspaceRepairAssignments> getRepairAssignments(boolean primaryRangeOnly,
 List<PrioritizedRepairPlan> repairPlans)

Description copied from interface: IAutoRepairTokenRangeSplitter

Split the token range you wish to repair into multiple assignments. The autorepair framework will repair the assignments from returned subrange iterator in the sequence it's provided.

Specified by:

getRepairAssignments in interface IAutoRepairTokenRangeSplitter

Parameters:

primaryRangeOnly - Whether to repair only this node's primary ranges or all of its ranges.

repairPlans - A list of ordered prioritized repair plans to generate assignments for in order.

Returns:

iterator of repair assignments, with each element representing a grouping of repair assignments for a given keyspace. The iterator is traversed lazily KeyspaceRepairAssignments at a time with the intent to try to get the most up-to-date representation of your data (e.g. how much data exists and is unrepaired at a given time).

getEstimatedBytes

protected static long getEstimatedBytes(List<RepairTokenRangeSplitter.SizedRepairAssignment> repairAssignments)

Parameters:

repairAssignments - The assignments to sum

Returns:

The sum of RepairTokenRangeSplitter.SizedRepairAssignment.getEstimatedBytes() of all given repairAssignments.

getRepairAssignmentsForTable

protected List<RepairTokenRangeSplitter.SizedRepairAssignment> getRepairAssignmentsForTable(KeyspaceRepairPlan repairPlan,
 String tableName,
 Range<Token> tokenRange)

getRepairAssignments

protected List<RepairTokenRangeSplitter.SizedRepairAssignment> getRepairAssignments(AutoRepairUtils.SizeEstimate estimate)

setParameter

public void setParameter(String key,
 String value)

Description copied from interface: IAutoRepairTokenRangeSplitter

Update a configuration parameter. This is meant to be used by nodetool setautorepairconfig to update configuration dynamically.

Specified by:

setParameter in interface IAutoRepairTokenRangeSplitter

Parameters:

key - parameter to update

value - The value to set to.

getParameters

public Map<String,String> getParameters()

Specified by:

getParameters in interface IAutoRepairTokenRangeSplitter

Returns:

custom configuration. This is meant to be used by nodetool getautorepairconfig for retrieving the splitter configuration.