Feedback-ID: i0fe9450f:Fastmail
Date: Tue, 4 Jun 2024 07:17:51 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Xing Guo <higuoxing@gmail.com>, pgsql-hackers@lists.postgresql.org
Subject: Re: Fix an incorrect assertion condition in mdwritev().
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On Sun, May 26, 2024 at 12:08:46AM -0400, Tom Lane wrote:
> After a few minutes' thought, how about:
>=20
> 	Assert((uint64) blocknum + (uint64) nblocks <=3D (uint64) mdnblocks(reln=
, forknum));
>=20
> This'd stop being helpful if we ever widen BlockNumber to 64 bits,
> but I think that's unlikely.  (Partitioning seems like a better answer
> for giant tables.)

No idea if this will happen or not, but that's not the only area where
we are going to need a native uint128 implementation to control the
overflows with uint64.

What you are suggesting is good enough for me, so I've applied on HEAD
a version using that.
--
Michael

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