private synchronized void scanIfNeeded() {
    if (!scanInProgress()) {
      recentlyUsedCounter.set(0);
      currentScan = executor.submit(this::scan);
    }
  }
Remove and return the Entry that is considered least recently used.
geode-core/src/main/java/org/apache/geode/internal/cache/eviction/LRUListWithAsyncSorting.java