Re: [PATCH] Improve EXPLAIN ANALYZE overhead by sampling

"Martijn van Oosterhout" <kleptog(at)svana(dot)org> wrote
>
> What it does behave normally for the first 50 tuples of any node, but
> after that it starts sampling at ever increasing intervals, the
> intervals controlled by an exponential function.
>

I got two questions after scanning the patch:

(1) For a node with 50 loops and another one 50+10^3 loops, the first
one will be measured 50 times and the second one will be measured 50+10
times? I am not sure if this is rational.

(2) Will this patch instruct multinode without interval? This is because
we always use ntuples=0 for multinode, so the tuplecount will not
change.

Maybe another way is to measure the cost of timing, then substruct it
from the result - but this is a hand-waiving only so far ...

Regards,
Qingqing