public void clearCaches(String hostName) {
    configsRecommendationResponse.clear();
    hostInfoCache.remove(hostName);
    LOG.info("Clear stack advisor caches, host: " + hostName);
  }
Returns an incremented requestId. Rollsover back to 0 in case the requestId >= recommendationsArtifactsrollovermax
@return {int requestId}
ambari-server/src/main/java/org/apache/ambari/server/api/services/stackadvisor/StackAdvisorHelper.java