Surprised to note that Expedited Retrieval in Glacier has not been explained in cloud guru. What is Expedited Retrieval in Glacier ?
Expedited — Expedited retrievals allow you to quickly access your data when occasional urgent requests for a subset of archives are required. For all but the largest archives (250 MB+), data accessed using Expedited retrievals are typically made available within 1–5 minutes. Provisioned Capacity ensures that retrieval capacity for Expedited retrievals is available when you need it.