diff --git a/solr/core/src/java/org/apache/solr/search/SolrIndexSearcher.java b/solr/core/src/java/org/apache/solr/search/SolrIndexSearcher.java
index de4d6bf59c2..7f155742ba5 100644
--- a/solr/core/src/java/org/apache/solr/search/SolrIndexSearcher.java
+++ b/solr/core/src/java/org/apache/solr/search/SolrIndexSearcher.java
@@ -33,6 +33,7 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicLong;
 
@@ -147,8 +148,7 @@ public class SolrIndexSearcher extends IndexSearcher implements Closeable, SolrI
   private final String path;
   private boolean releaseDirectory;
 
-  private volatile Map<Long,IndexFingerprint> maxVersionFingerprintCache = new HashMap<>();
-  private final Object fingerprintLock = new Object();
+  private final Map<Long, IndexFingerprint> maxVersionFingerprintCache = new ConcurrentHashMap<>();
 
   private static DirectoryReader getReader(SolrCore core, SolrIndexConfig config, DirectoryFactory directoryFactory,
       String path) throws IOException {
@@ -2379,22 +2379,16 @@ public class SolrIndexSearcher extends IndexSearcher implements Closeable, SolrI
    * gets a cached version of the IndexFingerprint for this searcher
    **/
   public IndexFingerprint getIndexFingerprint(long maxVersion) throws IOException {
+    IndexFingerprint fingerprint = maxVersionFingerprintCache.get(maxVersion);
+    if (fingerprint != null) return fingerprint;
     // possibly expensive, so prevent more than one thread from calculating it for this searcher
-    
-    // TODO what happens if updates came out of order, would cached fingerprint still be valid?
-    // May be caching fingerprint may lead more problems
-    IndexFingerprint fingerprint = maxVersionFingerprintCache.get(maxVersionFingerprintCache);
-    if(fingerprint == null) {
-      synchronized (fingerprintLock) {
-        if (maxVersionFingerprintCache.get(maxVersionFingerprintCache) == null) {
-          log.info("Fingerprint for max version: " + maxVersion + " not found in cache" );
-          maxVersionFingerprintCache.put(maxVersion, IndexFingerprint.getFingerprint(this, maxVersion));
-        }
-        fingerprint = maxVersionFingerprintCache.get(maxVersion) ;
-      }
+    synchronized (maxVersionFingerprintCache) {
+      fingerprint = maxVersionFingerprintCache.get(maxVersionFingerprintCache);
+      if (fingerprint != null) return fingerprint;
+      fingerprint = IndexFingerprint.getFingerprint(this, maxVersion);
+      maxVersionFingerprintCache.put(maxVersion, fingerprint);
+      return fingerprint;
     }
-
-    return fingerprint;
   }
 
   /////////////////////////////////////////////////////////////////////
diff --git a/solr/core/src/java/org/apache/solr/update/UpdateLog.java b/solr/core/src/java/org/apache/solr/update/UpdateLog.java
index ba25acfed58..0b4fc1895d2 100644
--- a/solr/core/src/java/org/apache/solr/update/UpdateLog.java
+++ b/solr/core/src/java/org/apache/solr/update/UpdateLog.java
@@ -952,7 +952,7 @@ public class UpdateLog implements PluginInfoInitialized {
 
       for (List<Update> singleList : updateList) {
         for (Update ptr : singleList) {
-          if(ptr.version > maxVersion) continue;
+          if(Math.abs(ptr.version) > Math.abs(maxVersion)) continue;
           ret.add(ptr.version);
           if (--n <= 0) return ret;
         }