Date: Tue, 9 Mar 2021 14:00:13 -0500
From: Bruce Momjian <bruce@momjian.us>
To: hemarbruno@gmail.com, pgsql-docs@lists.postgresql.org
Subject: Re: Transaction ID modulo
Message-ID: <20210309190013.GG26575@momjian.us>
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On Thu, Feb 18, 2021 at 01:54:37PM +0000, PG Doc comments form wrote:
> The following documentation comment has been logged on the website:
> 
> Page: https://www.postgresql.org/docs/13/routine-vacuuming.html
> Description:
> 
> Hello,
> 
> transaction ID modulo is not correct.
> 
> The sentence "Normal XIDs are compared using modulo-2^32 arithmetic" should
> be "Normal XIDs are compared using modulo-2^31 arithmetic"

Uh, we use full 32-bit values that wrap around; the top bit is just
another bit to us.  I think the docs are correct.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  The usefulness of a cup is in its emptiness, Bruce Lee