[PIP-78] Split the individual acknowledgments into multiple entries

[linlin]

Hi, community:
    Recently we encountered some problems when using individual
acknowledgments, such as:
when the amount of acknowledgment is large, entry writing fails; a large
amount of cache causes OOM, etc.
So I drafted a PIP in `
https://docs.google.com/document/d/1uQtyb8t6X04v2vrSrdGWLFkuCkBcGYZbqK8XsVJ4qkU/edit?usp=sharing`,
any voice is welcomed.