1. A method comprising: creating, by an apparatus operated by a service provider, a global storage instance in response to an end user request, wherein the global storage instance contains metadata of a storage layer including all storage nodes operated by the service provider for a plurality of clients, and wherein the global storage instance is delocalized from the storage nodes, wherein the storage layer includes a plurality of data centers at different geographic locations; receiving, by the apparatus, a database operation request from an operating system layer; mediating, by the apparatus, the database operation request between the operating system layer and the storage layer using the metadata of the storage nodes contained in the global storage instance; and upon a completion of the database operation request, initiating, by the apparatus, (1) updates to the metadata of the storage nodes contained in the global storage instance based on metadata locally updated at one or more of the storage nodes that completed the database operation request, (2) a synchronization of file indexes of all of the storage nodes, and (3) an account for and a rebalance of storage space available in all of the storage nodes.