private int getDelta() {
    Object d = lruDelta.get();
    lruDelta.set(null); // We only want the delta consumed once
    if (d == null) {
      return 0;
    }
    return (Integer) d;
  }
The delta produced during a put for activating LRU cannot be used while some outside party
(LocalRegion) has a segment locked... so we'll keep it in a thread local for a callback after
the segment is released.
geode-core/src/main/java/org/apache/geode/internal/cache/VMLRURegionMap.java