A storage aggregator controller, controller, comprising: a host interface configured to communicate over a computer network with one or more remote hosts; a storage device interface, configured to communicate locally with a plurality of local storage devices, separate from the one or more remote hosts, the storage devices having respective non-volatile memories; and aggregator control circuitry, configured to: manage the plurality of local storage devices for storage or retrieval of media objects, the plurality of storage devices coupled to the storage device interface, the aggregator control circuitry configured to present to the one or more remote hosts an abstracted logical address space that is mapped to a combination of physical address spaces of the plurality of storage devices, wherein the mapping of the abstracted logical address space to the physical address spaces is adjustable; select a component for computing metadata, the selected component for computing metadata being idle from performing storage operations and being selected from a group of components consisting of the aggregator control circuitry and one or more storage device controllers configured to control storage operations of one or more of the storage devices; and based on a result of the selecting, govern a computation, at the component selected from the group of components consisting of the aggregator control circuitry and the one or more storage device controllers of one or more of the storage devices, of metadata that defines content characteristics of the media objects that are retrieved from the plurality of storage devices or that are received from the one or more hosts over the computer network for storage in the plurality of storage devices. a host interface configured to communicate over a computer network with one or more remote hosts; a storage device interface, configured to communicate locally with a plurality of local storage devices, separate from the one or more remote hosts, the storage devices having respective non-volatile memories; and aggregator control circuitry, configured to: manage the plurality of local storage devices for storage or retrieval of media objects, the plurality of storage devices coupled to the storage device interface, the aggregator control circuitry configured to present to the one or more remote hosts an abstracted logical address space that is mapped to a combination of physical address spaces of the plurality of storage devices, wherein the mapping of the abstracted logical address space to the physical address spaces is adjustable; select a component for computing metadata, the selected component for computing metadata being idle from performing storage operations and being selected from a group of components consisting of the aggregator control circuitry and one or more storage device controllers configured to control storage operations of one or more of the storage devices; and based on a result of the selecting, govern a computation, at the component selected from the group of components consisting of the aggregator control circuitry and the one or more storage device controllers of one or more of the storage devices, of metadata that defines content characteristics of the media objects that are retrieved from the plurality of storage devices or that are received from the one or more hosts over the computer network for storage in the plurality of storage devices. manage the plurality of local storage devices for storage or retrieval of media objects, the plurality of storage devices coupled to the storage device interface, the aggregator control circuitry configured to present to the one or more remote hosts an abstracted logical address space that is mapped to a combination of physical address spaces of the plurality of storage devices, wherein the mapping of the abstracted logical address space to the physical address spaces is adjustable; select a component for computing metadata, the selected component for computing metadata being idle from performing storage operations and being selected from a group of components consisting of the aggregator control circuitry and one or more storage device controllers configured to control storage operations of one or more of the storage devices; and based on a result of the selecting, govern a computation, at the component selected from the group of components consisting of the aggregator control circuitry and the one or more storage device controllers of one or more of the storage devices, of metadata that defines content characteristics of the media objects that are retrieved from the plurality of storage devices or that are received from the one or more hosts over the computer network for storage in the plurality of storage devices.