Re: ModifyTable overheads in generic plans

Hi,

On 2021-04-06 19:24:11 -0400, Tom Lane wrote:
> I also could not get excited about postponing initialization of RETURNING
> or WITH CHECK OPTIONS expressions.  I grant that that can be helpful
> when those features are used, but I doubt that RETURNING is used that
> heavily, and WITH CHECK OPTIONS is surely next door to nonexistent
> in performance-critical queries.

FWIW, there's a number of ORMs etc that use it on every insert (there's
not really a better way to get the serial when you also want to do
pipelining).

> nparts    TPS
> 0    12152
> 10    8672
> 100    2753
> 1000    314
> 
> and after the two patches I just pushed, it looks like:
> 
> 0    12105
> 10    9928
> 100    5433
> 1000    938
> 
> So while there's certainly work left to do, that's not bad for
> some low-hanging-fruit grabbing.

Nice. 3x at the upper end is pretty good.

Greetings,

Andres Freund