Re: tuple statistics update

Hi,

2017-04-19 16:37 GMT+02:00 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:

> Tom DalPozzo <t(dot)dalpozzo(at)gmail(dot)com> writes:
> > 2017-04-18 22:06 GMT+02:00 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
> >> If your session is just sitting, that's not surprising. I think stats
> >> updates are only transmitted to the collector at transaction end (and
> >> even then, only if it's been at least N msec since the last transmission
> >> from the current session).
>
> > Hi, my transaction ended, that I waited 1 min and queried the stat.
> > I had to wait for session end in order to see the updeted stats.
> > Did you mean "...to the collector at SESSION end"?
>
> No, I meant what I said. No amount of just-sitting will cause a session
> to do something: it either transmits stats at transaction end or it
> doesn't because it thinks it's too soon since its last update. If you
> want to force out the stats, you could wait a second or so and then
> do a dummy transaction (even "select 1" will do, in testing).
>
> BTW, a quick look at the code says the threshold is 500 msec, ie,
> stats are sent only if it's been at least half a second since the
> session's last report.
>

I tried with a dummy select with no success. I detailed my test in my
answer to Adrian Klaver.
I'll avoid to duplicate it here.
Regards
Pupillo

>
> regards, tom lane
>