code: void evictCache(Path hdfsPath) throws IOException {
      CacheEntry c = cacheMap.remove(hdfsPath);
      if (c != null) {
        cacheSize.addAndGet(-c.entrySize);
        if (evictionIface != null) {
          evictionIface.evictCache(c.hdfsPath, c.localPath, c.entrySize);
        }
        localMetrics.numEvict++;
        if (LOG.isDebugEnabled()) {
          LOG.debug("LookasideCache removed path:" + hdfsPath +
                    " freed up size: " + c.entrySize);
        }
      }
    }
docs: Evicts an entry from the cache. This calls back into
  the application to indicate that a cache entry has been
  reclaimed.