Date: Fri, 19 Jun 2026 13:43:22 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Fujii Masao <masao.fujii@gmail.com>
Cc: wenhui qiu <qiuwenhuifx@gmail.com>,
	Shinya Kato <shinya11.kato@gmail.com>, pgsql-hackers@postgresql.org
Subject: Re: enhance wraparound warnings
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On Sat, Jun 20, 2026 at 03:13:23AM +0900, Fujii Masao wrote:
> The percentage is calculated as (xidWrapLimit - xid) divided by half
> of the ID space. This represents the remaining ID space before wraparound,
> not the percentage of IDs that are still available for use. Since
> PostgreSQL stops assigning new XIDs/MultiXactIds at the stop limit
> before reaching the wraparound limit, the current wording could be
> interpreted as overstating how many IDs remain usable.
> 
> So, how about changing the wording to match the calculation? For example:
> 
>     Approximately XX.XX% of transaction ID space remains before wraparound.
> 
> and similarly for MultiXactIds.

That seems reasonable to me, thanks.

-- 
nathan