Horton

Re: POC: make mxidoff 64 bits

Heikki Linnakangas <hlinnaka@iki.fi>

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From: Heikki Linnakangas <hlinnaka@iki.fi>
To: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, Maxim Orlov <orlovmg@gmail.com>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Alexander Korotkov <aekorotkov@gmail.com>, wenhui qiu <qiuwenhuifx@gmail.com>, Postgres hackers <pgsql-hackers@lists.postgresql.org>
Date: 2025-12-10T19:19:18Z
Lists: pgsql-hackers

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On 09/12/2025 14:00, Heikki Linnakangas wrote:
> 1. Currently, at multixid wraparound, MultiXactState->nextMXact goes to 
> 0, which is invalid. All the readers must be prepared for that, and skip 
> over the 0. That's error-prone, we've already missed that a few times. 
> Let's change things so that the code that *writes* MultiXactState- 
>  >nextMXact skips over the zero already.

Here's a patch for that. Does anyone see a problem with this?

- Heikki