Miner block budget spend down

[kantai]

The current default behavior of miners is to include as many transactions they can in the early block of the tenure within some “time limit” that they measure from wall clock time. This leads to spikiness in the block budget consumption, because miners are mostly able to fill their budgets in one or two blocks.

An alternative miner heuristic would reserve some block space for transactions arriving later with higher fees. In this model, the miner sets a target budget when mining equal to, e.g., 50% of the tenure budget (measured in any dimension). Afterwards, the next time they build a block, they set a target budget of 75% of the tenure budget (i.e., the next block will by itself have up to 25% of the tenure budget), and the next time they build a block, they set a target budget of 87.5%, etc. The reason to use an exponential target curve here is that on each block assembly, the miner is faced with the same trade-off (i.e., it is a recursive choice): how much of the block budget do I consume now, versus waiting for the possibility of a higher fee transaction? 50% is probably too “present weighted” – something like 25% could be better (i.e., consume 25% of the remaining budget with each block).