A method, non-transitory computer readable medium and storage server computing device that stores an identifier for a file system block evicted from a buffer cache in an entry in a table. The file system block is inserted into a victim cache hosted by an ephemeral block-level storage device by invoking a function provided by an application programming interface (API). The API exposes the ephemeral block-level storage device to a virtual storage appliance via an operating system of the storage server computing device. The entry in the table is updated to include location(s) on the ephemeral block-level storage device at which one or more portions of the file system block are stored, the location(s) returned in response to the function invocation. By this technology, performance of the virtual storage appliance is significantly improved, resulting in lower latency for client devices requesting data in a cloud storage environment.