public void refreshLastModifiedTime() {
    for (Account account : idToAccountMap.values()) {
      lastModifiedTime = Math.max(lastModifiedTime, account.getLastModifiedTime());
      for (Container container : account.getAllContainers()) {
        lastModifiedTime = Math.max(lastModifiedTime, container.getLastModifiedTime());
      }
    }
  }
Refreshes the lastModifiedTime of {@link Account}s and {@link Container}s in the cache. This is expected to be
called after account metadata is fetched from db periodically.
ambry-account/src/main/java/com/github/ambry/account/AccountInfoMap.java