meld vs cruz and when to include balanced tree data in afterimage

[dotnwat]

meld is probably not storing the result of balancing in the after image, but rather balancing on meld. when cruz replays we rebalance like meld, but then we also produce an afterimage that contains the rebalancing effects. we don't really have that fine grained pre-balance image to save. so we are writing a lot more than needed. one way to alleviate this would be to batch up changes into a larger delta that would absorb a lot of reblances.

would it be possible to store smaller afterimages in the log by doing something analgous where the affects of rebalancing are only in memory? its like a reverse ephemeral image.