A second timeout of file_timeout length is needed to avoid the stat when hoarding. i.e. if time.now > next_stat, and next_stat is set to time.now + timeout when the stat takes place. Without this every request for an environment also results in a stat. This state-timeout could use the normal file_timeout (default 15s). Longer term, the file_timeout will not be used for every file (since env watching will be replaced by directory env), so it can be repurposed for this rather than adding yet another time-out value.