Zeugswetter Andreas ADI SD wrote: > POSIX_FADV_WILLNEED definitely sounds very interesting, but: > > I think this interface was intended to hint larger areas (megabytes). > But the "wishful" thinking was not to hint seq scans, but to advise > single 8k pages.
Surely POSIX_FADV_SEQUENTIAL is the one intended to hint seq scans, and POSIX_FADV_RANDOM to hint random access. No? ISTM, _WILLNEED seems just right for small random-access blocks. Anyway, for those who want to see what they do in Linux, http://www.gelato.unsw.edu.au/lxr/source/mm/fadvise.c Pretty scary that Bruce said it could make older linuxes dump core - there isn't a lot of code there. ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
