Magnus Hagander wrote:
> O_DIRECT helps us when we're not going to read the file again, because
> we don't waste cache on it. If we are, which is the case here, it
> should be really bad for performance, since we actually have to do a
> physical read.
>
> Incidentally, that should also apply to general WAL when archive_mdoe
> is on. Do we optimize for that?
Hmm, no we don't. We do take that into account so that we refrain from
issuing posix_fadvice(DONTNEED) if archive_mode is on, but we don't
disable O_DIRECT. Maybe we should..
-- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com