@Override
  public String toString() {
    return "SamzaResourceRequest{" +
            "numCores=" + numCores +
            ", memoryMB=" + memoryMB +
            ", preferredHost='" + preferredHost + '\'' +
            ", requestId='" + requestId + '\'' +
            ", processorId=" + processorId +
            ", requestTimestampMs=" + requestTimestamp +
            ", faultDomains=" + faultDomains.toString() +
            '}';
  }
The timestamp in millis when the request was created.
samza-core/src/main/java/org/apache/samza/clustermanager/SamzaResourceRequest.java