Re: The unused_oids script should have a reminder to use the 8000-8999 OID range

From: Peter Geoghegan <pg(at)bowt(dot)ie>
To: Michael Paquier <michael(at)paquier(dot)xyz>
Cc: Julien Rouhaud <rjuju123(at)gmail(dot)com>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, PostgreSQL Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: The unused_oids script should have a reminder to use the 8000-8999 OID range
Date: 2019-08-04 03:25:03
Message-ID: CAH2-Wzn8MLxRgY+LXB+az0NZz77PKPxSSeCoFKsL=2nKsS6FPg@mail.gmail.com
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On Sat, Aug 3, 2019 at 7:48 PM Michael Paquier <michael(at)paquier(dot)xyz> wrote:
> Why choosing a random position within [8000,9999]? This leads to the
> following messages for example with multiple runs, which is confusing:
> Suggested random unused OID: 9473 (527 consecutive OID(s) available
> Suggested random unused OID: 8159 (31 consecutive OID(s) available
> Suggested random unused OID: 9491 (509 consecutive OID(s) available
>
> Wouldn't it be better to choose the lowest position in the development
> range, and then adapt the suggestion based on that?

No, it wouldn't. The entire point of suggesting a totally random OID
is that it minimizes the probability of a collision among concurrently
developed patches, per the policy established by commit a6417078 --
what you suggest would defeat the very purpose of this patch. In fact,
having everybody see the same suggestion from unused_oids would
*maximize* the number of OID collisions.

> We could
> recommend the range if there are at least 10 OIDs available in the
> range from the lowest position, and there are few patches eating more
> than 5-10 OIDs at once.

That sounds like an over-engineered solution to a problem that doesn't exist.

--
Peter Geoghegan

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