Re: surprisingly slow creation of gist index used in exclude constraint

Chris Withers <chris@withers.org> writes:
>       It has 4.1 million rows in it and while importing the data only
>       takes a couple of minutes, when I did a test load into the new
>       cluster, building the mkt_profile_period_col1_col4_col2_chan_excl
>       index for the exclude constraint took 15 hours.

Don't recall for sure, but I think GIST index build is sensitive
to the maintenance_work_mem setting; did you have that cranked up?

>     - failing that, what can I do to import and then create the index
>       in the background?

CREATE INDEX CONCURRENTLY, perhaps.

            regards, tom lane