From: Tom Lane <tgl@sss.pgh.pa.us>
To: Bruno Wolff III <bruno@wolff.to>
cc: pgsql-general@lists.postgresql.org, pgsql-hackers@lists.postgresql.org
Subject: Re: Should pg 11 use a lot more memory building an spgist index?
In-reply-to: <20181026112314.GA8199@wolff.to>
References: <20181024012314.GA27428@wolff.to> <19003.1540370028@sss.pgh.pa.us>
 <20181024083748.GA3296@wolff.to> <19088.1540372871@sss.pgh.pa.us>
 <20181025174306.GA3184@wolff.to> <24288.1540545369@sss.pgh.pa.us>
 <20181026112314.GA8199@wolff.to>
Comments: In-reply-to Bruno Wolff III <bruno@wolff.to>
	message dated "Fri, 26 Oct 2018 06:23:14 -0500"
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Date: Fri, 26 Oct 2018 13:44:07 +0100
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Bruno Wolff III <bruno@wolff.to> writes:
>   Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Hmm, in my hands this produces the same size leak (~28GB) in either v10
>> or v11.  In HEAD, somebody's made it even worse (~43GB).  So this is
>> certainly pretty broken, but I'm not sure why it seems worse to you in
>> v11 than before.

> As a short term work around, could I create the index first and use 
> insert statements, each in their own transaction, to get the table loaded 
> with the index?

Yes; it might also be that you don't even need to break it up into
separate statements.

> Is the issue on Fedora taking very long to build a normal spgist index for 
> network addresses worth pursuing separately, or is it likely to be the same 
> underlying cause?

This issue only applies if it was an exclusion constraint.  If you saw
slowness or bloat with a plain index, that would be worth investigating
separately.

			regards, tom lane