Question about max prefetch

[realitix]

I would like to know precisely how max_prefetch works. If I set workers = 6, for example, thus six worker processes, and I do not set max_prefetch, how will the task distribution among the 6 workers happen? Will a single worker retrieve all the tasks, or will the task distribution be balanced among the 6? For instance, if we have max_async_task set to 6, should max_prefetch also be set to 6 ?

Thanks