SOLR-9844: Improve FieldCache usage api response formatting and show total size information

lucene/core/src/java/org/apache/lucene/index/SegmentCoreReaders.java

@@ -56,6 +56,7 @@ final class SegmentCoreReaders {
   final TermVectorsReader termVectorsReaderOrig;
   final PointsReader pointsReader;
   final Directory cfsReader;
+  final String segment;
   /** 
    * fieldinfos for this core: means gen=-1.
    * this is the exact fieldinfos these codec components saw at write.
@@ -98,6 +99,8 @@ final class SegmentCoreReaders {
         cfsDir = dir;
       }
 
+      segment = si.info.name;
+
       coreFieldInfos = codec.fieldInfosFormat().read(cfsDir, si.info, "", context);
       
       final SegmentReadState segmentReadState = new SegmentReadState(cfsDir, si.info, coreFieldInfos, context);
@@ -192,4 +195,9 @@ final class SegmentCoreReaders {
   void removeCoreClosedListener(CoreClosedListener listener) {
     coreClosedListeners.remove(listener);
   }
+
+  @Override
+  public String toString() {
+    return "SegmentCoreReader(" + segment + ")";
+  }
 }

solr/CHANGES.txt

@@ -164,6 +164,9 @@ New Features
 * SOLR-5043: New solr.dns.prevent.reverse.lookup system property that can be used to prevent long core
   (re)load delays on systems with missconfigured hostname/DNS (hossman)
 
+* SOLR-9844: FieldCache information fetched via the mbeans handler or seen via the UI now displays the total size used.
+  The individual cache entries in the response are now formatted better as well. (Varun Thacker)
+
 Optimizations
 ----------------------
 * SOLR-9704: Facet Module / JSON Facet API: Optimize blockChildren facets that have

solr/core/src/java/org/apache/solr/search/SolrFieldCacheMBean.java

@@ -64,11 +64,13 @@ public class SolrFieldCacheMBean implements JmxAugmentedSolrInfoMBean {
     if (listEntries) {
       String[] entries = UninvertingReader.getUninvertedStats();
       stats.add("entries_count", entries.length);
+      stats.add("total_size", UninvertingReader.getTotalSize());
       for (int i = 0; i < entries.length; i++) {
         stats.add("entry#" + i, entries[i]);
       }
     } else {
       stats.add("entries_count", UninvertingReader.getUninvertedStatsSize());
+      stats.add("total_size", UninvertingReader.getTotalSize());
     }
     return stats;
   }

solr/core/src/java/org/apache/solr/uninverting/FieldCache.java

@@ -384,7 +384,7 @@ public interface FieldCache {
       return custom;
     }
 
-    public Object getValue() {
+    public Accountable getValue() {
       return value;
     }
 
@@ -399,15 +399,11 @@ public interface FieldCache {
     
     @Override
     public String toString() {
-      StringBuilder b = new StringBuilder(250);
-      b.append("'").append(getReaderKey()).append("'=>");
-      b.append("'").append(getFieldName()).append("',");
-      b.append(getCacheType()).append(",").append(getCustom());
-      b.append("=>").append(getValue().getClass().getName()).append("#");
-      b.append(System.identityHashCode(getValue()));
-      
+      StringBuilder b = new StringBuilder(100);
+      b.append("segment='").append(getReaderKey().toString()).append("', ");
+      b.append("field='").append(getFieldName()).append("', ");
       String s = getEstimatedSize();
-      b.append(" (size =~ ").append(s).append(')');
+      b.append("size =~ ").append(s);
 
       return b.toString();
     }

solr/core/src/java/org/apache/solr/uninverting/FieldCacheSanityChecker.java

@@ -27,6 +27,7 @@ import java.util.Set;
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.index.IndexReaderContext;
 import org.apache.lucene.store.AlreadyClosedException;
+import org.apache.lucene.util.Accountable;
 import org.apache.lucene.util.MapOfSets;
 import org.apache.solr.uninverting.FieldCache.CacheEntry;
 
@@ -103,7 +104,7 @@ final class FieldCacheSanityChecker {
     // iterate over all the cacheEntries to get the mappings we'll need
     for (int i = 0; i < cacheEntries.length; i++) {
       final CacheEntry item = cacheEntries[i];
-      final Object val = item.getValue();
+      final Accountable val = item.getValue();
 
       // It's OK to have dup entries, where one is eg
       // float[] and the other is the Bits (from

solr/core/src/java/org/apache/solr/uninverting/UninvertingReader.java

@@ -37,6 +37,7 @@ import org.apache.lucene.index.LeafReader;
 import org.apache.lucene.index.NumericDocValues;
 import org.apache.lucene.index.SortedDocValues;
 import org.apache.lucene.index.SortedSetDocValues;
+import org.apache.lucene.util.RamUsageEstimator;
 import org.apache.solr.uninverting.FieldCache.CacheEntry;
 
 /**
@@ -386,4 +387,13 @@ public class UninvertingReader extends FilterLeafReader {
   public static int getUninvertedStatsSize() {
     return FieldCache.DEFAULT.getCacheEntries().length;
   }
+
+  public static String getTotalSize() {
+    CacheEntry[] entries = FieldCache.DEFAULT.getCacheEntries();
+    long totalBytesUsed = 0;
+    for (int i = 0; i < entries.length; i++) {
+      totalBytesUsed += entries[i].getValue().ramBytesUsed();
+    }
+    return RamUsageEstimator.humanReadableUnits(totalBytesUsed);
+  }
 }

solr/core/src/test/org/apache/solr/search/TestSolrFieldCacheMBean.java

@@ -76,6 +76,7 @@ public class TestSolrFieldCacheMBean extends SolrTestCaseJ4 {
     SolrFieldCacheMBean mbean = new SolrFieldCacheMBean();
     NamedList stats = checkJmx ? mbean.getStatisticsForJmx() : mbean.getStatistics();
     assert(new Integer(stats.get("entries_count").toString()) > 0);
+    assertNotNull(stats.get("total_size"));
     assertNull(stats.get("entry#0"));
   }
 }