1. A method for reducing perceived read latency, comprising: receiving a read request from a reader; issuing, via one or more processors and in response to the read request, input-output requests (IOs) to storage media; and prior to completing the read request, returning a response to the reader based on one or more conditions of a predefined first policy, wherein the first policy is defined based on at least one of a percentage of data corresponding to the read request available to return, a relative distribution of unavailable data in a scatter-gather array configured to store data associated with the read request, and an estimated time duration until full satisfaction of the read request, wherein, prior to returning the read request, unfilled pages of the scatter-gather array are unmapped.