tweaking the co-efficient

core/src/main/java/hudson/tasks/Fingerprinter.java

@@ -344,9 +344,8 @@ public class Fingerprinter extends Recorder implements Serializable, DependecyDe
 
         public void onLoad() {
             // share data structure with nearby builds, but to keep lazy loading efficient,
-            // don't go back the history forever. By RAND!=0, 4 neighboring builds will share
-            // the data structure, so we'll get good enough saving.
-            if (rand.nextInt(4)!=0) {
+            // don't go back the history forever.
+            if (rand.nextInt(2)!=0) {
                 Run pb = build.getPreviousBuild();
                 if (pb!=null) {
                     FingerprintAction a = pb.getAction(FingerprintAction.class);