org.apache.cassandra.service.reads.repair

Class ReadOnlyReadRepair<E extends Endpoints<E>,P extends ReplicaPlan.ForRead<E,P>>

java.lang.Object

org.apache.cassandra.service.reads.repair.AbstractReadRepair<E,P>

org.apache.cassandra.service.reads.repair.ReadOnlyReadRepair<E,P>

All Implemented Interfaces:

ReadRepair<E,P>

public class ReadOnlyReadRepair<E extends Endpoints<E>,P extends ReplicaPlan.ForRead<E,P>>
extends AbstractReadRepair<E,P>

Only performs the collection of data responses and reconciliation of them, doesn't send repair mutations to replicas. This preserves write atomicity, but doesn't provide monotonic quorum reads

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.cassandra.service.reads.repair.ReadRepair

ReadRepair.Factory

Field Summary

Fields inherited from class org.apache.cassandra.service.reads.repair.AbstractReadRepair

cfs, command, logger, queryStartNanoTime, replicaPlan

Method Summary

Modifier and Type	Method and Description
void	awaitWrites() Block on any mutations (or timeout) we sent out to repair replicas in ReadRepair.repairPartition(org.apache.cassandra.db.DecoratedKey, java.util.Map<org.apache.cassandra.locator.Replica, org.apache.cassandra.db.Mutation>, org.apache.cassandra.locator.ReplicaPlan.ForWrite)
UnfilteredPartitionIterators.MergeListener	getMergeListener(P replicaPlan) Used by DataResolver to generate corrections as the partition iterator is consumed
void	maybeSendAdditionalWrites() If it looks like we might not receive acks for all the repair mutations we sent out, combine all the unacked mutations and send them to the minority of nodes not involved in the read repair data read / write cycle.
void	repairPartition(DecoratedKey partitionKey, java.util.Map<Replica,Mutation> mutations, ReplicaPlan.ForWrite writePlan) Repairs a partition _after_ receiving data responses.

Methods inherited from class org.apache.cassandra.service.reads.repair.AbstractReadRepair

awaitReads, maybeSendAdditionalReads, replicaPlan, startRepair

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.cassandra.service.reads.repair.ReadRepair

create

Method Detail

getMergeListener

public UnfilteredPartitionIterators.MergeListener getMergeListener(P replicaPlan)

Description copied from interface: ReadRepair

Used by DataResolver to generate corrections as the partition iterator is consumed

maybeSendAdditionalWrites

public void maybeSendAdditionalWrites()

Description copied from interface: ReadRepair

If it looks like we might not receive acks for all the repair mutations we sent out, combine all the unacked mutations and send them to the minority of nodes not involved in the read repair data read / write cycle. We will accept acks from them in lieu of acks from the initial mutations sent out, so long as we receive the same number of acks as repair mutations transmitted. This prevents misbehaving nodes from killing a quorum read, while continuing to guarantee monotonic quorum reads

repairPartition

public void repairPartition(DecoratedKey partitionKey,
                            java.util.Map<Replica,Mutation> mutations,
                            ReplicaPlan.ForWrite writePlan)

Description copied from interface: ReadRepair

Repairs a partition _after_ receiving data responses. This method receives replica list, since we will block repair only on the replicas that have responded.

awaitWrites

public void awaitWrites()

Description copied from interface: ReadRepair

Block on any mutations (or timeout) we sent out to repair replicas in ReadRepair.repairPartition(org.apache.cassandra.db.DecoratedKey, java.util.Map<org.apache.cassandra.locator.Replica, org.apache.cassandra.db.Mutation>, org.apache.cassandra.locator.ReplicaPlan.ForWrite)