On Thu, Apr 21, 2016 at 3:31 PM, Alvaro Herrera <alvhe...@2ndquadrant.com> wrote: > Robert Haas wrote: >> On Thu, Apr 21, 2016 at 2:22 PM, Andres Freund <and...@anarazel.de> wrote: >> > On 2016-04-21 14:15:53 -0400, Robert Haas wrote: >> >> On Tue, Mar 29, 2016 at 7:53 PM, Thomas Munro >> >> <thomas.mu...@enterprisedb.com> wrote: >> >> > On the WaitEventSet thread I posted a small patch to add kqueue >> >> > support[1]. Since then I peeked at how some other software[2] >> >> > interacts with kqueue and discovered that there are platforms >> >> > including NetBSD where kevent.udata is an intptr_t instead of a void >> >> > *. Here's a version which should compile there. Would any NetBSD >> >> > user be interested in testing this? (An alternative would be to make >> >> > configure to test for this with some kind of AC_COMPILE_IFELSE >> >> > incantation but the steamroller cast is simpler.) >> >> >> >> Did you code this up blind or do you have a NetBSD machine yourself? >> > >> > RMT, what do you think, should we try to get this into 9.6? It's >> > feasible that the performance problem 98a64d0bd713c addressed is also >> > present on free/netbsd. >> >> My personal opinion is that it would be a reasonable thing to do if >> somebody can demonstrate that it actually solves a real problem. >> Absent that, I don't think we should rush it in. > > My first question is whether there are platforms that use kqueue on > which the WaitEventSet stuff proves to be a bottleneck. I vaguely > recall that MacOS X in particular doesn't scale terribly well for other > reasons, and I don't know if anybody runs *BSD in large machines. > > On the other hand, there's plenty of hackers running their laptops on > MacOS X these days, so presumably any platform dependent problem would > be discovered quickly enough. As for NetBSD, it seems mostly a fringe > platform, doesn't it? We would discover serious dependency problems > quickly enough on the buildfarm ... except that the only netbsd > buildfarm member hasn't reported in over two weeks. > > Am I mistaken in any of these points? > > (Our coverage of the BSD platforms leaves much to be desired FWIW.)
My impression is that the Linux problem only manifested itself on large machines. I might be wrong about that. But if that's true, then we might not see regressions on other platforms just because people aren't running those operating systems on big enough hardware. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
