Re: Performance degradation in commit ac1d794

On 2016-03-19 15:43:27 +0530, Amit Kapila wrote:
> On Sat, Mar 19, 2016 at 12:40 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
> >
> > On March 18, 2016 11:52:08 PM PDT, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
> wrote:
> > >> >Won't the new code needs to ensure that ResetEvent(latchevent)
> > >should
> > >> >get
> > >> >called in case WaitForMultipleObjects() comes out when both
> > >> >pgwin32_signal_event and latchevent are signalled at the same time?

> > >> WaitForMultiple only reports the readiness of on event at a time, no?
> > >>
> > >
> > >I don't think so, please read link [1] with a focus on below paragraph
> > >which states how it reports the readiness or signaled state when
> > >multiple
> > >objects become signaled.
> > >
> > >"When *bWaitAll* is *FALSE*, this function checks the handles in the
> > >array
> > >in order starting with index 0, until one of the objects is signaled.
> > >If
> > >multiple objects become signaled, the function returns the index of the
> > >first handle in the array whose object was signaled."

I think this is just incredibly bad documentation. See
https://blogs.msdn.microsoft.com/oldnewthing/20150409-00/?p=44273
(Raymond Chen can be considered an authority here imo).

Andres