Understanding of DeepSpeeChat “ Inference”

[gosth]

I just started learning gpt field, and read the article about DeepSpeeChat
There are some doubts about the understanding of “ Inference”.
In my opinion，“Inference” is an online serving process, like this:

In article, "Inference" is a sub-process of RLHF training， like this：

some questions：
1、 "Inference" in DeepSpeeChat, is a sub-process of RLHF training. So it is a part of training（an offline process）？
2、 The DeepSpeedChat can improve efficiency.Is it means DeepSpeedChat can only imporve the efficiency of offline process(traing), not online process(online serving)?
3、 “The Hybrid Engine” in article， can only imporve the efficiency of offline process(traing), not online process(online serving)?