Remove deprecated query cache settings

core/src/main/java/org/elasticsearch/cluster/ClusterModule.java

@@ -186,7 +186,6 @@ public class ClusterModule extends AbstractModule {
         registerIndexDynamicSetting(IndexSettings.INDEX_TRANSLOG_DURABILITY, Validator.EMPTY);
         registerIndexDynamicSetting(IndicesWarmer.INDEX_WARMER_ENABLED, Validator.EMPTY);
         registerIndexDynamicSetting(IndicesRequestCache.INDEX_CACHE_REQUEST_ENABLED, Validator.BOOLEAN);
-        registerIndexDynamicSetting(IndicesRequestCache.DEPRECATED_INDEX_CACHE_REQUEST_ENABLED, Validator.BOOLEAN);
         registerIndexDynamicSetting(UnassignedInfo.INDEX_DELAYED_NODE_LEFT_TIMEOUT_SETTING, Validator.TIME);
         registerIndexDynamicSetting(DefaultSearchContext.MAX_RESULT_WINDOW, Validator.POSITIVE_INTEGER);
     }

core/src/main/java/org/elasticsearch/indices/cache/request/IndicesRequestCache.java

@@ -79,13 +79,9 @@ public class IndicesRequestCache extends AbstractComponent implements RemovalLis
      * since we are checking on the cluster state IndexMetaData always.
      */
     public static final String INDEX_CACHE_REQUEST_ENABLED = "index.requests.cache.enable";
-    @Deprecated
-    public static final String DEPRECATED_INDEX_CACHE_REQUEST_ENABLED = "index.cache.query.enable";
     public static final String INDICES_CACHE_REQUEST_CLEAN_INTERVAL = "indices.requests.cache.clean_interval";
 
     public static final String INDICES_CACHE_QUERY_SIZE = "indices.requests.cache.size";
-    @Deprecated
-    public static final String DEPRECATED_INDICES_CACHE_QUERY_SIZE = "indices.cache.query.size";
     public static final String INDICES_CACHE_QUERY_EXPIRE = "indices.requests.cache.expire";
 
     private static final Set<SearchType> CACHEABLE_SEARCH_TYPES = EnumSet.of(SearchType.QUERY_THEN_FETCH, SearchType.QUERY_AND_FETCH);
@@ -113,19 +109,7 @@ public class IndicesRequestCache extends AbstractComponent implements RemovalLis
         this.threadPool = threadPool;
         this.cleanInterval = settings.getAsTime(INDICES_CACHE_REQUEST_CLEAN_INTERVAL, TimeValue.timeValueSeconds(60));
 
-        String size = settings.get(INDICES_CACHE_QUERY_SIZE);
-        if (size == null) {
-            size = settings.get(DEPRECATED_INDICES_CACHE_QUERY_SIZE);
-            if (size != null) {
-                deprecationLogger.deprecated("The [" + DEPRECATED_INDICES_CACHE_QUERY_SIZE
-                        + "] settings is now deprecated, use [" + INDICES_CACHE_QUERY_SIZE + "] instead");
-            }
-        }
-        if (size == null) {
-            // this cache can be very small yet still be very effective
-            size = "1%";
-        }
-        this.size = size;
+        this.size = settings.get(INDICES_CACHE_QUERY_SIZE, "1%");
 
         this.expire = settings.getAsTime(INDICES_CACHE_QUERY_EXPIRE, null);
         buildCache();
@@ -135,18 +119,7 @@ public class IndicesRequestCache extends AbstractComponent implements RemovalLis
     }
 
     private boolean isCacheEnabled(Settings settings, boolean defaultEnable) {
-        Boolean enable = settings.getAsBoolean(INDEX_CACHE_REQUEST_ENABLED, null);
-        if (enable == null) {
-            enable = settings.getAsBoolean(DEPRECATED_INDEX_CACHE_REQUEST_ENABLED, null);
-            if (enable != null) {
-                deprecationLogger.deprecated("The [" + DEPRECATED_INDEX_CACHE_REQUEST_ENABLED
-                        + "] settings is now deprecated, use [" + INDEX_CACHE_REQUEST_ENABLED + "] instead");
-            }
-        }
-        if (enable == null) {
-            enable = defaultEnable;
-        }
-        return enable;
+        return settings.getAsBoolean(INDEX_CACHE_REQUEST_ENABLED, defaultEnable);
     }
 
     private void buildCache() {

docs/reference/migration/migrate_3_0.asciidoc

@@ -206,6 +206,11 @@ The `index.translog.flush_threshold_ops` setting is not supported anymore. In or
 growth use `index.translog.flush_threshold_size` instead. Changing the translog type with `index.translog.fs.type` is not supported
 anymore, the `buffered` implementation is now the only available option and uses a fixed `8kb` buffer.
 
+==== Request Cache Settings
+
+The deprecated settings `index.cache.query.enable` and `indices.cache.query.size` have been removed and are replaced with
+`index.requests.cache.enable` and `indices.requests.cache.size` respectively.
+
 [[breaking_30_mapping_changes]]
 === Mapping changes