Scripting: Per-context script cache, default off

server/src/main/java/org/elasticsearch/common/settings/AbstractScopedSettings.java

@@ -224,6 +224,18 @@ public synchronized void addSettingsUpdateConsumer(Consumer<Settings> consumer,
         addSettingsUpdater(Setting.groupedSettingsUpdater(consumer, settings));
     }
 
+    /**
+     * Adds a settings consumer that is only executed if any setting in the supplied list of settings is changed. In that case all the
+     * settings are specified in the argument are returned.  The validator is run across all specified settings before the settings are
+     * applied.
+     *
+     * Also automatically adds empty consumers for all settings in order to activate logging
+     */
+    public synchronized void addSettingsUpdateConsumer(Consumer<Settings> consumer, List<? extends Setting<?>> settings,
+                                                       Consumer<Settings> validator) {
+        addSettingsUpdater(Setting.groupedSettingsUpdater(consumer, settings, validator));
+    }
+
     /**
      * Adds a settings consumer for affix settings. Affix settings have a namespace associated to it that needs to be available to the
      * consumer in order to be processed correctly.

server/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java

@@ -364,10 +364,13 @@ public void apply(Settings value, Settings current, Settings previous) {
             NetworkService.TCP_RECEIVE_BUFFER_SIZE,
             IndexSettings.QUERY_STRING_ANALYZE_WILDCARD,
             IndexSettings.QUERY_STRING_ALLOW_LEADING_WILDCARD,
+            ScriptService.SCRIPT_GENERAL_CACHE_SIZE_SETTING,
+            ScriptService.SCRIPT_GENERAL_CACHE_EXPIRE_SETTING,
+            ScriptService.SCRIPT_GENERAL_MAX_COMPILATIONS_RATE_SETTING,
             ScriptService.SCRIPT_CACHE_SIZE_SETTING,
             ScriptService.SCRIPT_CACHE_EXPIRE_SETTING,
+            ScriptService.SCRIPT_MAX_COMPILATIONS_RATE_SETTING,
             ScriptService.SCRIPT_MAX_SIZE_IN_BYTES,
-            ScriptService.SCRIPT_MAX_COMPILATIONS_RATE,
             ScriptService.TYPES_ALLOWED_SETTING,
             ScriptService.CONTEXTS_ALLOWED_SETTING,
             IndicesService.INDICES_CACHE_CLEAN_INTERVAL_SETTING,

server/src/main/java/org/elasticsearch/common/settings/Setting.java

@@ -668,7 +668,12 @@ public String toString() {
 
     static AbstractScopedSettings.SettingUpdater<Settings> groupedSettingsUpdater(Consumer<Settings> consumer,
                                                                                   final List<? extends Setting<?>> configuredSettings) {
+        return groupedSettingsUpdater(consumer, configuredSettings, (v) -> {});
+    }
 
+    static AbstractScopedSettings.SettingUpdater<Settings> groupedSettingsUpdater(Consumer<Settings> consumer,
+                                                                                  final List<? extends Setting<?>> configuredSettings,
+                                                                                  Consumer<Settings> validator) {
         return new AbstractScopedSettings.SettingUpdater<Settings>() {
 
             private Settings get(Settings settings) {
@@ -691,6 +696,7 @@ public boolean hasChanged(Settings current, Settings previous) {
 
             @Override
             public Settings getValue(Settings current, Settings previous) {
+                validator.accept(current);
                 return get(current);
             }
 

server/src/main/java/org/elasticsearch/script/ScriptCache.java

@@ -40,53 +40,47 @@ public class ScriptCache {
 
     private static final Logger logger = LogManager.getLogger(ScriptService.class);
 
-    private Cache<CacheKey, Object> cache;
-    private final ScriptMetrics scriptMetrics = new ScriptMetrics();
+    private final Cache<CacheKey, Object> cache;
+    private final ScriptMetrics scriptMetrics;
 
     private final Object lock = new Object();
 
-    private Tuple<Integer, TimeValue> rate;
+    // Mutable fields
     private long lastInlineCompileTime;
     private double scriptsPerTimeWindow;
-    private double compilesAllowedPerNano;
 
-    // Cache settings
-    private int cacheSize;
-    private TimeValue cacheExpire;
+    // Cache settings or derived from settings
+    final int cacheSize;
+    final TimeValue cacheExpire;
+    final Tuple<Integer, TimeValue> rate;
+    private final double compilesAllowedPerNano;
 
-    public ScriptCache(
+    ScriptCache(
             int cacheMaxSize,
             TimeValue cacheExpire,
             Tuple<Integer, TimeValue> maxCompilationRate
     ) {
+        this.cacheSize = cacheMaxSize;
+        this.cacheExpire = cacheExpire;
+
         CacheBuilder<CacheKey, Object> cacheBuilder = CacheBuilder.builder();
-        if (cacheMaxSize >= 0) {
-            cacheBuilder.setMaximumWeight(cacheMaxSize);
+        if (this.cacheSize >= 0) {
+            cacheBuilder.setMaximumWeight(this.cacheSize);
         }
 
-        if (cacheExpire.getNanos() != 0) {
-            cacheBuilder.setExpireAfterAccess(cacheExpire);
+        if (this.cacheExpire.getNanos() != 0) {
+            cacheBuilder.setExpireAfterAccess(this.cacheExpire);
         }
 
-        logger.debug("using script cache with max_size [{}], expire [{}]", cacheMaxSize, cacheExpire);
+        logger.debug("using script cache with max_size [{}], expire [{}]", this.cacheSize, this.cacheExpire);
         this.cache = cacheBuilder.removalListener(new ScriptCacheRemovalListener()).build();
 
-        this.lastInlineCompileTime = System.nanoTime();
-
-        this.cacheSize = cacheMaxSize;
-        this.cacheExpire = cacheExpire;
-        this.setMaxCompilationRate(maxCompilationRate);
-    }
+        this.rate = maxCompilationRate;
+        this.scriptsPerTimeWindow = this.rate.v1();
+        this.compilesAllowedPerNano = ((double) rate.v1()) / rate.v2().nanos();
 
-    private Cache<CacheKey,Object> buildCache() {
-        CacheBuilder<CacheKey, Object> cacheBuilder = CacheBuilder.builder();
-        if (cacheSize >= 0) {
-            cacheBuilder.setMaximumWeight(cacheSize);
-        }
-        if (cacheExpire.getNanos() != 0) {
-            cacheBuilder.setExpireAfterAccess(cacheExpire);
-        }
-        return cacheBuilder.removalListener(new ScriptCacheRemovalListener()).build();
+        this.lastInlineCompileTime = System.nanoTime();
+        this.scriptMetrics = new ScriptMetrics();
     }
 
     <FactoryType> FactoryType compile(
@@ -185,22 +179,6 @@ void checkCompilationLimit() {
         }
     }
 
-    /**
-     * This configures the maximum script compilations per five minute window.
-     *
-     * @param newRate the new expected maximum number of compilations per five minute window
-     */
-    void setMaxCompilationRate(Tuple<Integer, TimeValue> newRate) {
-        synchronized (lock) {
-            this.rate = newRate;
-            // Reset the counter to allow new compilations
-            this.scriptsPerTimeWindow = rate.v1();
-            this.compilesAllowedPerNano = ((double) rate.v1()) / newRate.v2().nanos();
-
-            this.cache = buildCache();
-        }
-    }
-
     /**
      * A small listener for the script cache that calls each
      * {@code ScriptEngine}'s {@code scriptRemoved} method when the