Re: Should pg 11 use a lot more memory building an spgist index?

On Tue, Oct 23, 2018 at 20:23:14 -0500,
  Bruno Wolff III <bruno@wolff.to> wrote:
>While reloading a database cluster to move from 10.5 to 11, I'm 
>getting out of memory crashes that I did see when doing reloads on pg 
>10.
>The statement flagged in the log is this:
>2018-10-23 16:44:34.815 CDT [126839] STATEMENT:  ALTER TABLE ONLY public.iplocation
>	    ADD CONSTRAINT overlap EXCLUDE USING spgist (network WITH &&);
>
>iplocation has 4398722 rows.

I'm trying to reproduce this on my desktop but so far it isn't producing 
the same issue. The database is still loading after 9 hours, but it looks 
like it got past the point where the problem index was created. (I'm not 
sure how to check if the index has really finished being created, but \d 
shows it as existing.)

I'll know better tomorrow.

My workstation is using the Fedora version of postgresql 11 which might 
have some relevant difference from the pgdg version for rhel7. I still 
have a number of things I can try, but they might take significant time 
to run and I might not get a reasonable test case for a while.