On 2017-08-14 12:28:39 -0400, Tom Lane wrote: > Robert Haas <robertmh...@gmail.com> writes: > > On Mon, Aug 14, 2017 at 12:16 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > >> Just FYI, the only values being reported by buildfarm animals are > >> "posix", "sysv", and "windows". So while mmap may be a thing, > >> it's an untested thing. > > > I'm pretty sure I dev-tested it before committing anything, but, > > certainly, having ongoing BF coverage woudn't be a bad thing. > > Looking closer, the reason those are the only reported values is > that those are the only possible results from initdb's > choose_dsm_implementation(). So the real question here is whether > "mmap" should be considered to dominate "sysv" if it's available.
No mmap isn't a good option - it's file backed mmap, rather than anonymous mmap. To my knowledge there's no good portable way to use anonymous mmap to share memory across processes unless established before a fork(). > If so, why isn't choose_dsm_implementation() trying it; and if not, > why are we carrying it? I think the idea was that there might be platforms that require it, but ... Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers