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Re: Missing query plan for auto_explain. - Mailing list pgsql-general

From Maxim Boguk
Subject Re: Missing query plan for auto_explain.
Date
Msg-id CAK-MWwQ3sD_s2HYePjOOHeEeO3fxQPpUzxrhcUEaVyTC+xh4LQ@mail.gmail.com
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In response to Re: Missing query plan for auto_explain.  (Matheus Martin <matheus.martin@voidbridge.com>)
Responses Re: Missing query plan for auto_explain.
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On Thu, Sep 8, 2022 at 1:18 PM Matheus Martin <matheus.martin@voidbridge.com> wrote:
We do have JIT enabled `jit=on` with `jit_above_cost=100000`.

I am sorry but I don't quite understand what role JIT plays in this situation with `auto_explain`. Could you please elaborate on that?


In your log - time spent during the execution stage (where auto-exlain can help) but during the bind/planning stage (e.g. generation of plan).
So you have a problem not with slow query execution, but with slow query planning, so autoexplain cannot help in that case.
JIT is one possible explanation of planning stage slowdown.

Can you run explain (analyze, costs, buffers, timing) of your query?
And check how long the planning stage took and check if JIT was used or not (and how much time spent during JIT if it had been used).



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Maxim Boguk
Senior Postgresql DBA
https://dataegret.com/

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