Lacked "memLimitMB" field when using db.hostInfo()

Hi everyone, I am beginner to mongodb.
I use mongodb ver 4.0.6 on ubuntu 16.04. I read this article: and repeated it. But I did not see any field name “memLimitMB” in output.
Below is my result’s screenshot, pls help me. I can not explain it.

Hi @Vu_Van_Th_ng,

memLimitMB is starting from 4.0.9 and as you’re using 4.0.6 it’s not visible. memLimitMB


Thank you so much for your helping!