From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Heinemann, Manfred (IMS)" <HeinemannM@imsweb.com>
cc: "pgsql-admin@lists.postgresql.org" <pgsql-admin@lists.postgresql.org>
Subject: Re: Function search_path
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Comments: In-reply-to "Heinemann, Manfred (IMS)" <HeinemannM@imsweb.com>
	message dated "Thu, 22 Mar 2018 19:30:56 -0000"
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Date: Sun, 25 Mar 2018 13:13:31 -0400
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"Heinemann, Manfred (IMS)" <HeinemannM@imsweb.com> writes:
> Here is an example where I can show significant extra memory consumption=
 when setting search_path on a function:

I got around to testing this example today, and I don't see what you're
seeing --- the memory consumption seems stable, and about the same with
or without the "SET search_path" clause.

You didn't specify exactly how to do this bit:

--populate 1,000,000 rows with random values from 1,000 surnames for 'SURN=
AME'

so I did it like this:

INSERT INTO test_search_path(date_last_modified, last_name)
select clock_timestamp(), (random()*1000)::int::text
from generate_series(1,1000000);

The example doesn't seem like it'd be terribly data-dependent, but
maybe that's wrong?

Also, I assume you're running a reasonably up-to-date PG release,
otherwise I'd be wondering about leaks in the GIN index AM; we've
fixed some issues of that sort in GIN bulk updates in the past.
But again, it's not clear what the connection to a function SET
clause would be.  So I lack a plausible theory at the moment.

			regards, tom lane