org.apache.lucene.search
Class CachingWrapperFilter.DeletesMode

java.lang.Object
  org.apache.lucene.util.Parameter
      org.apache.lucene.search.CachingWrapperFilter.DeletesMode

All Implemented Interfaces:

Serializable

Enclosing class:

CachingWrapperFilter

public static final class CachingWrapperFilter.DeletesMode
extends Parameter
implements Serializable

Expert: Specifies how new deletions against a reopened reader should be handled.

The default is IGNORE, which means the cache entry will be re-used for a given segment, even when that segment has been reopened due to changes in deletions. This is a big performance gain, especially with near-real-timer readers, since you don't hit a cache miss on every reopened reader for prior segments.

However, in some cases this can cause invalid query results, allowing deleted documents to be returned. This only happens if the main query does not rule out deleted documents on its own, such as a toplevel ConstantScoreQuery. To fix this, use RECACHE to re-create the cached filter (at a higher per-reopen cost, but at faster subsequent search performance), or use DYNAMIC to dynamically intersect deleted docs (fast reopen time but some hit to search performance).

See Also:

Serialized Form

Field Summary

static CachingWrapperFilter.DeletesMode	DYNAMIC
static CachingWrapperFilter.DeletesMode	IGNORE
static CachingWrapperFilter.DeletesMode	RECACHE

Method Summary

Methods inherited from class org.apache.lucene.util.Parameter

readResolve, toString

Methods inherited from class java.lang.Object

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

Field Detail

IGNORE

public static CachingWrapperFilter.DeletesMode IGNORE

RECACHE

public static CachingWrapperFilter.DeletesMode RECACHE

DYNAMIC

public static CachingWrapperFilter.DeletesMode DYNAMIC