Message-ID: <a4cd767db6a12df2c924caa6bbdf59f8986f7bbc.camel@cybertec.at>
Subject: Re: SubtransControlLock and performance problems
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Pavel Stehule <pavel.stehule@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: Lars Aksel Opsahl <Lars.Opsahl@nibio.no>,
	"pgsql-performance@lists.postgresql.org"
	 <pgsql-performance@lists.postgresql.org>
Date: Tue, 18 Feb 2020 18:27:24 +0100
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On Mon, 2020-02-17 at 19:41 +0100, Pavel Stehule wrote:
> I tested 
> 
> CREATE OR REPLACE FUNCTION public.fx(integer)
>  RETURNS void
>  LANGUAGE plpgsql
> AS $function$
> begin
>   for i in 1..$1 loop
>   begin
>     insert into foo values(i);
> exception when others then
>   raise notice 'yyy';
> end;
> end loop;
> end;
> $function$
> 
> and I don't see any significant difference between numbers less than 64 and higher

Did you have several concurrent sessions accessing the rows that others created?

Yours,
Laurenz Albe
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