diff --git a/source/net/yacy/kelondro/blob/Heap.java b/source/net/yacy/kelondro/blob/Heap.java
index db4b4bdb6..d16c252ef 100644
--- a/source/net/yacy/kelondro/blob/Heap.java
+++ b/source/net/yacy/kelondro/blob/Heap.java
@@ -113,7 +113,7 @@ public final class Heap extends HeapModifier implements BLOB {
      * @return the number of BLOBs in the heap
      */
     @Override
-    public synchronized int size() {
+    public int size() {
         return super.size() + ((this.buffer == null) ? 0 : this.buffer.size());
     }
 
diff --git a/source/net/yacy/kelondro/index/RAMIndex.java b/source/net/yacy/kelondro/index/RAMIndex.java
index 51f979766..7435c8c1a 100644
--- a/source/net/yacy/kelondro/index/RAMIndex.java
+++ b/source/net/yacy/kelondro/index/RAMIndex.java
@@ -325,7 +325,7 @@ public final class RAMIndex implements Index, Iterable<Row.Entry> {
     }
 
     @Override
-    public final synchronized int size() {
+    public final int size() {
         if (this.index0 != null && this.index1 == null) {
             return this.index0.size();
         }
@@ -337,7 +337,7 @@ public final class RAMIndex implements Index, Iterable<Row.Entry> {
     }
 
     @Override
-    public final synchronized boolean isEmpty() {
+    public final boolean isEmpty() {
         if (this.index0 != null && this.index1 == null) {
             return this.index0.isEmpty();
         }
diff --git a/source/net/yacy/kelondro/index/RAMIndexCluster.java b/source/net/yacy/kelondro/index/RAMIndexCluster.java
index 3a89793dd..f64b61b10 100644
--- a/source/net/yacy/kelondro/index/RAMIndexCluster.java
+++ b/source/net/yacy/kelondro/index/RAMIndexCluster.java
@@ -337,26 +337,20 @@ public final class RAMIndexCluster implements Index, Iterable<Row.Entry>, Clonea
     @Override
     public final int size() {
         int c = 0;
-        synchronized (this.cluster) {
-            for (final RAMIndex i: this.cluster) if (i != null) c += i.size();
-        }
+        for (final RAMIndex i: this.cluster) if (i != null) c += i.size();
         return c;
     }
 
     @Override
     public long mem() {
         long m = 0;
-        synchronized (this.cluster) {
-            for (final RAMIndex i: this.cluster) if (i != null)  m += i.mem();
-        }
+        for (final RAMIndex i: this.cluster) if (i != null)  m += i.mem();
         return m;
     }
 
     @Override
     public final boolean isEmpty() {
-        synchronized (this.cluster) {
-            for (final RAMIndex i: this.cluster) if (i != null && !i.isEmpty()) return false;
-        }
+        for (final RAMIndex i: this.cluster) if (i != null && !i.isEmpty()) return false;
         return true;
     }