public Set<InternalDistributedMember> advisePreloadeds() {
    return adviseFilter(profile -> {
      assert profile instanceof CacheProfile;
      CacheProfile cp = (CacheProfile) profile;
      return cp.dataPolicy.withPreloaded();
    });
  }
Provide only the preloadeds given a set of existing memberIds

@return the set of preloaded's memberIds
@since GemFire prPersistSprint1
geode-core/src/main/java/org/apache/geode/internal/cache/CacheDistributionAdvisor.java