org.elasticsearch.indices.cache.request

クラス IndicesRequestCache

java.lang.Object

org.elasticsearch.common.component.AbstractComponent

org.elasticsearch.indices.cache.request.IndicesRequestCache

すべての実装されたインタフェース:

com.google.common.cache.RemovalListener<IndicesRequestCache.Key,IndicesRequestCache.Value>

public class IndicesRequestCache
extends AbstractComponent
implements com.google.common.cache.RemovalListener<IndicesRequestCache.Key,IndicesRequestCache.Value>

The indices request cache allows to cache a shard level request stage responses, helping with improving similar requests that are potentially expensive (because of aggs for example). The cache is fully coherent with the semantics of NRT (the index reader version is part of the cache key), and relies on size based eviction to evict old reader associated cache entries as well as scheduler reaper to clean readers that are no longer used or closed shards.

Currently, the cache is only enabled for count requests, and can only be opted in on an index level setting that can be dynamically changed and defaults to false.

There are still several TODOs left in this class, some easily addressable, some more complex, but the support is functional.

ネストされたクラスのサマリー

ネストされたクラス

修飾子とタイプ	クラスと説明
static class	IndicesRequestCache.Key
static class	IndicesRequestCache.Value

フィールドのサマリー

フィールド

修飾子とタイプ	フィールドと説明
static String	DEPRECATED_INDEX_CACHE_REQUEST_ENABLED 非推奨です。
static String	DEPRECATED_INDICES_CACHE_QUERY_SIZE 非推奨です。
static String	INDEX_CACHE_REQUEST_ENABLED A setting to enable or disable request caching on an index level.
static String	INDICES_CACHE_QUERY_CONCURRENCY_LEVEL
static String	INDICES_CACHE_QUERY_EXPIRE
static String	INDICES_CACHE_QUERY_SIZE
static String	INDICES_CACHE_REQUEST_CLEAN_INTERVAL

クラスから継承されたフィールド org.elasticsearch.common.component.AbstractComponent

deprecationLogger, logger, settings

コンストラクタのサマリー

コンストラクタ

コンストラクタと説明
IndicesRequestCache(Settings settings, ClusterService clusterService, ThreadPool threadPool)

メソッドのサマリー

修飾子とタイプ	メソッドと説明
boolean	canCache(ShardSearchRequest request, SearchContext context) Can the shard request be cached at all?
void	clear(IndexShard shard)
void	close()
void	loadIntoContext(ShardSearchRequest request, SearchContext context, QueryPhase queryPhase) Loads the cache result, computing it if needed by executing the query phase and otherwise deserializing the cached value into the context's query result.
void	onRemoval(com.google.common.cache.RemovalNotification<IndicesRequestCache.Key,IndicesRequestCache.Value> notification)

クラスから継承されたメソッド org.elasticsearch.common.component.AbstractComponent

logDeprecatedSetting, logRemovedSetting, nodeName

クラスから継承されたメソッド java.lang.Object

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

フィールドの詳細

INDEX_CACHE_REQUEST_ENABLED

public static final String INDEX_CACHE_REQUEST_ENABLED

A setting to enable or disable request caching on an index level. Its dynamic by default since we are checking on the cluster state IndexMetaData always.

関連項目:

定数フィールド値

DEPRECATED_INDEX_CACHE_REQUEST_ENABLED

@Deprecated
public static final String DEPRECATED_INDEX_CACHE_REQUEST_ENABLED

非推奨です。

関連項目:

定数フィールド値

INDICES_CACHE_REQUEST_CLEAN_INTERVAL

public static final String INDICES_CACHE_REQUEST_CLEAN_INTERVAL

関連項目:

定数フィールド値

INDICES_CACHE_QUERY_SIZE

public static final String INDICES_CACHE_QUERY_SIZE

関連項目:

定数フィールド値

DEPRECATED_INDICES_CACHE_QUERY_SIZE

@Deprecated
public static final String DEPRECATED_INDICES_CACHE_QUERY_SIZE

非推奨です。

関連項目:

定数フィールド値

INDICES_CACHE_QUERY_EXPIRE

public static final String INDICES_CACHE_QUERY_EXPIRE

関連項目:

定数フィールド値

INDICES_CACHE_QUERY_CONCURRENCY_LEVEL

public static final String INDICES_CACHE_QUERY_CONCURRENCY_LEVEL

関連項目:

定数フィールド値

コンストラクタの詳細

IndicesRequestCache

@Inject
public IndicesRequestCache(Settings settings,
                                   ClusterService clusterService,
                                   ThreadPool threadPool)

メソッドの詳細

close

public void close()

clear

public void clear(IndexShard shard)

onRemoval

public void onRemoval(com.google.common.cache.RemovalNotification<IndicesRequestCache.Key,IndicesRequestCache.Value> notification)

定義:

onRemoval インタフェース内 com.google.common.cache.RemovalListener<IndicesRequestCache.Key,IndicesRequestCache.Value>

canCache

public boolean canCache(ShardSearchRequest request,
                        SearchContext context)

Can the shard request be cached at all?

loadIntoContext

public void loadIntoContext(ShardSearchRequest request,
                            SearchContext context,
                            QueryPhase queryPhase)
                     throws Exception

Loads the cache result, computing it if needed by executing the query phase and otherwise deserializing the cached value into the context's query result. The combination of load + compute allows to have a single load operation that will cause other requests with the same key to wait till its loaded an reuse the same cache.

例外:

Exception