org.apache.cassandra.service.reads

Class ShortReadProtection

java.lang.Object

org.apache.cassandra.service.reads.ShortReadProtection

public class ShortReadProtection
extends java.lang.Object

We have a potential short read if the result from a given node contains the requested number of rows (i.e. it has stopped returning results due to the limit), but some of them haven't made it into the final post-reconciliation result due to other nodes' row, range, and/or partition tombstones. If that is the case, then that node may have more rows that we should fetch, as otherwise we could ultimately return fewer rows than required. Also, those additional rows may contain tombstones which which we also need to fetch as they may shadow rows or partitions from other replicas' results, which we would otherwise return incorrectly.

Constructor Summary

Constructors

Constructor and Description
ShortReadProtection()

Method Summary

Modifier and Type	Method and Description
static UnfilteredPartitionIterator	extend(Replica source, java.lang.Runnable preFetchCallback, UnfilteredPartitionIterator partitions, ReadCommand command, DataLimits.Counter mergedResultCounter, long queryStartNanoTime, boolean enforceStrictLiveness)

Methods inherited from class java.lang.Object

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

Constructor Detail

ShortReadProtection

public ShortReadProtection()

Method Detail

extend

public static UnfilteredPartitionIterator extend(Replica source,
                                                 java.lang.Runnable preFetchCallback,
                                                 UnfilteredPartitionIterator partitions,
                                                 ReadCommand command,
                                                 DataLimits.Counter mergedResultCounter,
                                                 long queryStartNanoTime,
                                                 boolean enforceStrictLiveness)