1. A processor-implemented method for outputting map-reduce jobs to an archive file, comprising: providing, by a processor, an archive manager and exposing an interface to be called from map-reduce jobs to output to the archive file in a map-reduce distributed file system; using a buffering database as a temporary cache to buffer updates to the archive file; handling by the archive manager calls from map-reduce jobs to allow: reading directly from the archive file or from a job index in the buffering database; and writing to the job index in the buffering database used as a temporary cache to buffer the updates; outputting the updates from the job index to the archive file, wherein the archive file is a single, zip formatted file, and the updates are concurrently written to the archive file from a plurality of map-reduced tasks running within a single map-reduced job while the single map-reduced job is running; and wherein handling by the archive manager calls from map-reduce jobs further comprises: receiving a write call for a task of a map-reduce job; connecting to the buffering database; looking up a unique token for a map-reduce job at a pending index provided at the buffering database; and writing to the job index provided at the buffering database.