Re: Timing of 'SELECT 1'

Merlin Moncure wrote:
> > > The problem with gprof is that I am going to see all the backend
> startup
> > > stuff too, no? Is there a way to get a dump just the run of the
> query?
> >
> > I was sort of lurking on this thread, waiting to see what became of
> it.
> > Did
> > nobody actually come to a conclusion on what that "last msec" was
> from?
>
> I think the consensus was it was coming from the network layer somehow.
> If that's the case (it probably is), there isn't a whole lot that can be
> done about it except to bypass it using server side functions and such.
>

I did a little more research and found an unusual cause. It turns out
enabling log_parser/executor_status itself makes SELECT 1's log_duration
go from 0.296 to 1.156 so the slowness I was seeing for SELECT 1 was
from the measurement, not slowness in the normal code path.

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