Add to node stats the number of times field cache was evicted due to memory constraints, closes elastic#603.

Author: kimchy

modules/elasticsearch/src/main/java/org/elasticsearch/index/cache/field/data/FieldDataCache.java

@@ -42,6 +42,8 @@ public interface FieldDataCache extends IndexComponent, CloseableComponent {
 
     void clearUnreferenced();
 
+    long evictions();
+
     long sizeInBytes();
 
     long sizeInBytes(String fieldName);

modules/elasticsearch/src/main/java/org/elasticsearch/index/cache/field/data/none/NoneFieldDataCache.java

@@ -69,4 +69,8 @@ public class NoneFieldDataCache extends AbstractIndexComponent implements FieldD
     @Override public long sizeInBytes(String fieldName) {
         return 0;
     }
+
+    @Override public long evictions() {
+        return 0;
+    }
 }

modules/elasticsearch/src/main/java/org/elasticsearch/index/cache/field/data/resident/ResidentFieldDataCache.java

@@ -45,4 +45,8 @@ public class ResidentFieldDataCache extends AbstractConcurrentMapFieldDataCache
     @Override public String type() {
         return "resident";
     }
+
+    @Override public long evictions() {
+        return 0;
+    }
 }

modules/elasticsearch/src/main/java/org/elasticsearch/index/cache/field/data/soft/SoftFieldDataCache.java

@@ -19,6 +19,7 @@
 
 package org.elasticsearch.index.cache.field.data.soft;
 
+import org.elasticsearch.common.collect.MapEvictionListener;
 import org.elasticsearch.common.collect.MapMaker;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Settings;
@@ -27,22 +28,34 @@
 import org.elasticsearch.index.field.data.FieldData;
 import org.elasticsearch.index.settings.IndexSettings;
 
+import javax.annotation.Nullable;
 import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.atomic.AtomicLong;
 
 /**
  * @author kimchy (shay.banon)
  */
-public class SoftFieldDataCache extends AbstractConcurrentMapFieldDataCache {
+public class SoftFieldDataCache extends AbstractConcurrentMapFieldDataCache implements MapEvictionListener<String, FieldData> {
+
+    private final AtomicLong evictions = new AtomicLong();
 
     @Inject public SoftFieldDataCache(Index index, @IndexSettings Settings indexSettings) {
         super(index, indexSettings);
     }
 
     @Override protected ConcurrentMap<String, FieldData> buildFieldDataMap() {
-        return new MapMaker().softValues().makeMap();
+        return new MapMaker().softValues().evictionListener(this).makeMap();
+    }
+
+    @Override public long evictions() {
+        return evictions.get();
     }
 
     @Override public String type() {
         return "soft";
     }
+
+    @Override public void onEviction(@Nullable String s, @Nullable FieldData fieldData) {
+        evictions.incrementAndGet();
+    }
 }

modules/elasticsearch/src/main/java/org/elasticsearch/index/cache/field/data/weak/WeakFieldDataCache.java

@@ -19,6 +19,7 @@
 
 package org.elasticsearch.index.cache.field.data.weak;
 
+import org.elasticsearch.common.collect.MapEvictionListener;
 import org.elasticsearch.common.collect.MapMaker;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Settings;
@@ -27,22 +28,34 @@
 import org.elasticsearch.index.field.data.FieldData;
 import org.elasticsearch.index.settings.IndexSettings;
 
+import javax.annotation.Nullable;
 import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.atomic.AtomicLong;
 
 /**
  * @author kimchy (shay.banon)
  */
-public class WeakFieldDataCache extends AbstractConcurrentMapFieldDataCache {
+public class WeakFieldDataCache extends AbstractConcurrentMapFieldDataCache implements MapEvictionListener<String, FieldData> {
+
+    private final AtomicLong evictions = new AtomicLong();
 
     @Inject public WeakFieldDataCache(Index index, @IndexSettings Settings indexSettings) {
         super(index, indexSettings);
     }
 
     @Override protected ConcurrentMap<String, FieldData> buildFieldDataMap() {
-        return new MapMaker().weakValues().makeMap();
+        return new MapMaker().weakValues().evictionListener(this).makeMap();
     }
 
     @Override public String type() {
         return "weak";
     }
+
+    @Override public long evictions() {
+        return evictions.get();
+    }
+
+    @Override public void onEviction(@Nullable String s, @Nullable FieldData fieldData) {
+        evictions.incrementAndGet();
+    }
 }

modules/elasticsearch/src/main/java/org/elasticsearch/indices/IndicesStats.java

@@ -43,13 +43,17 @@ public class IndicesStats implements Streamable, Serializable, ToXContent {
 
     private ByteSizeValue filterCacheSize;
 
+    private long fieldCacheEvictions;
+
     IndicesStats() {
     }
 
-    public IndicesStats(ByteSizeValue storeSize, ByteSizeValue fieldCacheSize, ByteSizeValue filterCacheSize) {
+    public IndicesStats(ByteSizeValue storeSize, ByteSizeValue fieldCacheSize, ByteSizeValue filterCacheSize,
+                        long fieldCacheEvictions) {
         this.storeSize = storeSize;
         this.fieldCacheSize = fieldCacheSize;
         this.filterCacheSize = filterCacheSize;
+        this.fieldCacheEvictions = fieldCacheEvictions;
     }
 
     /**
@@ -82,6 +86,14 @@ public ByteSizeValue getFilterCacheSize() {
         return this.filterCacheSize;
     }
 
+    public long fieldCacheEvictions() {
+        return this.fieldCacheEvictions;
+    }
+
+    public long getFieldCacheEvictions() {
+        return fieldCacheEvictions();
+    }
+
     public static IndicesStats readIndicesStats(StreamInput in) throws IOException {
         IndicesStats stats = new IndicesStats();
         stats.readFrom(in);
@@ -104,6 +116,7 @@ public static IndicesStats readIndicesStats(StreamInput in) throws IOException {
         builder.startObject(Fields.INDICES);
         builder.field(Fields.STORE_SIZE, storeSize.toString());
         builder.field(Fields.STORE_SIZE_IN_BYTES, storeSize.bytes());
+        builder.field(Fields.FIELD_CACHE_EVICTIONS, fieldCacheEvictions);
         builder.field(Fields.FIELD_CACHE_SIZE, fieldCacheSize.toString());
         builder.field(Fields.FIELD_CACHE_SIZE_IN_BYTES, fieldCacheSize.bytes());
         builder.field(Fields.FILTER_CACHE_SIZE, filterCacheSize.toString());
@@ -117,6 +130,7 @@ static final class Fields {
         static final XContentBuilderString STORE_SIZE_IN_BYTES = new XContentBuilderString("store_size_in_bytes");
         static final XContentBuilderString FIELD_CACHE_SIZE = new XContentBuilderString("field_cache_size");
         static final XContentBuilderString FIELD_CACHE_SIZE_IN_BYTES = new XContentBuilderString("field_cache_size_in_bytes");
+        static final XContentBuilderString FIELD_CACHE_EVICTIONS = new XContentBuilderString("field_cache_evictions");
         static final XContentBuilderString FILTER_CACHE_SIZE = new XContentBuilderString("filter_cache_size");
         static final XContentBuilderString FILTER_CACHE_SIZE_IN_BYTES = new XContentBuilderString("filter_cache_size_in_bytes");
     }

modules/elasticsearch/src/main/java/org/elasticsearch/indices/InternalIndicesService.java

@@ -156,6 +156,7 @@ public class InternalIndicesService extends AbstractLifecycleComponent<IndicesSe
 
     @Override public IndicesStats stats() {
         long storeTotalSize = 0;
+        long fieldCacheEvictions = 0;
         long fieldCacheTotalSize = 0;
         long filterCacheTotalSize = 0;
         for (IndexService indexService : indices.values()) {
@@ -166,10 +167,11 @@ public class InternalIndicesService extends AbstractLifecycleComponent<IndicesSe
                     // ignore
                 }
             }
+            fieldCacheEvictions += indexService.cache().fieldData().evictions();
             fieldCacheTotalSize += indexService.cache().fieldData().sizeInBytes();
             filterCacheTotalSize += indexService.cache().filter().sizeInBytes();
         }
-        return new IndicesStats(new ByteSizeValue(storeTotalSize), new ByteSizeValue(fieldCacheTotalSize), new ByteSizeValue(filterCacheTotalSize));
+        return new IndicesStats(new ByteSizeValue(storeTotalSize), new ByteSizeValue(fieldCacheTotalSize), new ByteSizeValue(filterCacheTotalSize), fieldCacheEvictions);
     }
 
     /**