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Date: Mon, 21 Oct 2024 09:40:14 +0400
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Subject: Re: type cache cleanup improvements
To: =?UTF-8?Q?Dagfinn_Ilmari_Manns=C3=A5ker?= <ilmari@ilmari.org>,
 Alexander Korotkov <aekorotkov@gmail.com>
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From: Andrei Lepikhov <lepihov@gmail.com>
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On 21/10/2024 06:32, Dagfinn Ilmari Mannsåker wrote:
> Alexander Korotkov <aekorotkov@gmail.com> writes:
> 
>> +static Oid *in_progress_list;
>> +static int	in_progress_list_len;
>> +static int	in_progress_list_maxlen;
> 
> Is there any particular reason not to use pg_list.h for this?
Sure. The type cache lookup has to be as much optimal as possible.
Using an array and relating sequential access to it, we avoid memory 
allocations and deallocations 99.9% of the time. Also, quick access to 
the single element (which we will have in real life almost all of the 
time) is much faster than employing list machinery.

-- 
regards, Andrei Lepikhov