Re: [PATCH] Support Int64 GUCs - Mailing list pgsql-hackers

From Nathan Bossart
Subject Re: [PATCH] Support Int64 GUCs
Date
Msg-id ZuLwp8SLShYtd-Xo@nathan
Whole thread Raw
List pgsql-hackers
On Thu, Sep 12, 2024 at 02:08:15PM +0300, Aleksander Alekseev wrote:
> Secondly, the following core GUCs are made 64-bit:
> 
> ```
> autovacuum_freeze_min_age
> autovacuum_freeze_max_age
> autovacuum_freeze_table_age
> autovacuum_multixact_freeze_min_age
> autovacuum_multixact_freeze_max_age
> autovacuum_multixact_freeze_table_age
> ```
> 
> I see several open questions with the patch in its current state.
> 
> Firstly, I'm not sure if it is beneficial to affect the named GUCs out
> of the context of the larger patchset. Perhaps we have better GUCs
> that could benefit from being 64-bit? Or should we just leave alone
> the core GUCs and focus on providing DefineCustomInt64Variable() ?

I don't understand why we would want to make these GUCs 64-bit.  All of the
allowed values fit in an int32, so AFAICT this would only serve to mislead
users into thinking they could set these much higher than they can/should.

TBH I'm quite skeptical that this would even be particularly useful for
extension authors.  In what cases would a floating point value not suffice?
I'm not totally opposed to the idea of 64-bit GUCs, but I'd like more
information about the motivation.

-- 
nathan



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