Subject: Re: Recursive query slow on strange conditions
To: pgsql-performance@lists.postgresql.org
References: <4a3b0246-f3ef-0767-62d1-6ceb4e2fc09c@thefreecat.org>
From: Jean-Christophe Boggio <postgresql@thefreecat.org>
Message-ID: <644c5b7f-aa5e-66bd-defa-e56a80bd9781@thefreecat.org>
Date: Mon, 4 May 2020 18:12:34 +0200
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Hello,

I have rewritten the function/query to make it a PLPGSQL function and 
split the query in ~20 smaller queries.

Now the problem of the JIT compiler kicking in also happens on PG 11.6
Although the 2 seconds induced delay is not a serious problem when I 
execute the query for thousands of items, it really becomes one when 
querying ONE item.

Is there a way to disable JIT (I use the apt.postgresql.org repository) 
in both 11.6 and 12.2 ? I would have liked to disable it on this 
particular query but maybe I could live with disabling JIT everywhere.

Thanks for your help,

JC