use nfsv3 for quicker response after mount, use tmpfs where you can, use sudo
drop large non-result data structures before passing back invoke to caller
drop unneeded extra directory, make it obvious where top per-thread dir is
remove unneeded extra dir level, optimize directory creation/cleanup, shrink buffers to reasonable size (speedup), disable calls to self.log.debug in fast path unless logging actually set to debug, self.dirs_on_demand added