Re: When do vacuumed pages/tuples become available for reuse?

On 2019-Apr-11, Tom Lane wrote:

> Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
> > On 2019-Apr-11, rihad wrote:
> >> 2019-04-11 19:39:44.450844500   tuples: 19150 removed, 2725811 remain, 465 are dead but not yet removable
>
> > What Jeff said. This vacuum spent a lot of time, only to remove miserly
> > 19k tuples, but 2.7M dead tuples remained ... probably because you have
> > long-running transactions preventing vacuum from removing them.
>
> I think you misread it --- I'm pretty sure "N remain" is referring
> to live tuples. Maybe we should adjust the wording to make that
> clearer?

Oh, I've been confused with that many times, Not good trying to decode
confusing messages while simultaneously figuring out trying to figure
out logical decoding bugs that have already been fixed :-(

Yeah, let's reword that. I've had to read the source half a dozen times
because I always forget what each number means.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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