[herriojr]

I haven't played with kafka in a while, but basically,

1. each group id represents a point in the stream that a consumer is processing off of. You could technically have multiple processes consuming off of a single group id.

2. there was a configuration on time to keep things there as well as space if I remember correctly, but basically, there has to be. There's a pretty hard limit on what all you can store on disk.

edit: changed consumer id to group id. If you want more info, feel free to ping me about the ecosystem