1. A method of improving recoverability of a dataset associated with a multi-tier storage system, the method comprising: storing to first storage updates to the dataset, wherein the dataset and a point-in-time copy of the dataset reside on second storage, wherein said dataset does not reside on said first storage, and the first storage provides higher reliability than the second storage; and recovering the dataset using at least a subset of the stored updates in combination with the point-in-time copy in the event that the dataset is lost.