On 2017-04-20 20:10:41 -0400, Tom Lane wrote: > Andres Freund <and...@anarazel.de> writes: > > On 2017-04-20 20:05:02 -0400, Tom Lane wrote: > >> Also, if it's not there we'd fall back to using plain poll(), which is > >> not so awful that we need to work hard to avoid it. I'd just as soon > >> keep the number of combinations down. > > > Just using fcntl(SET, CLOEXEC) wound't increase the number of > > combinations? > > True, if you just did it that way unconditionally. But doesn't that > require an extra kernel call per CreateWaitEventSet()?
It does - the question is whether that matters much. FE/BE uses a persistent wait set, but unfortunately much of other latch users don't. And some of them can be somewhat frequent - so I guess that'd possibly be measurable. Ok, so I'm on board with epoll1. If somebody were to change more frequent latch users to use persistent wait sets, that'd be good too. - Andres -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers