Thanks for your tips, As the article said, It uses the feature of sharding zone to split the database.collection which data would be stored diff zone such as named hot zone, warm zone, etc.
There are some ideas about Hot, warm, and cold data storage requirement as below:
The hot place just has the last data or the frequent read of data. It’not all data in this place.
It will transfer the hot data which doesn’t use during the period to a warm place and will be in a cold place finally and The hot place will erase the old data.
The data of cold place will store the hot place if the data have operation frequently