Subject: Re: jit and explain nontext
To: Justin Pryzby <pryzby@telsasoft.com>
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Cc: David Rowley <dgrowleyml@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>,
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From: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Organization: EnterpriseDB
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Date: Sat, 21 Nov 2020 08:39:11 +0100
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On 2020-11-20 17:16, Justin Pryzby wrote:
> It matters if it was planned with jit but executed without jit.
> 
> postgres=# DEALLOCATE p; SET jit=on; SET jit_above_cost=0; prepare p as select from generate_series(1,9); explain(format yaml) execute p; SET jit=off; explain(format yaml) execute p;
> 
> Patched shows this for both explains:
>     JIT:                              +
>       Functions: 3                    +
> 
> Unpatched shows only in the first case.

In this context, I don't see the point of this change.  If you set 
jit=off explicitly, then there is no need to clutter the EXPLAIN output 
with a bunch of zeroes about JIT.