A computer-implemented method, according to one embodiment, includes: sending one or more instructions to calculate a combined size of fragments included in the fragmented files, sending one or more instructions to designate a portion of cache which corresponds to at least the combined size of the fragments, sending one or more instructions to send a copy of each non-fragmented file from a first drive directly to a second drive in which the second sequential storage medium is loaded, sending one or more instructions to use the designated portion of the cache to accumulate the fragments included in the fragmented files, and sending one or more instructions to send a copy of each of the fragments corresponding to a given fragmented file from the cache to the second drive in response to determining that all of the fragments corresponding to the given fragmented file have been accumulated in the cache.