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Date: Mon, 17 Nov 2025 08:04:57 +0100
From: "Joel Jacobson" <joel@compiler.org>
To: pgsql-hackers <pgsql-hackers@postgresql.org>
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Subject: Re: Optimize LISTEN/NOTIFY
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 <https://www.postgresql.org/message-id/5c9a01fb-b777-4a08-bc82-1b9b5a4b732b%40app.fastmail.com>
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On Sat, Nov 15, 2025, at 22:53, Joel Jacobson wrote:
> On Fri, Nov 14, 2025, at 17:01, Joel Jacobson wrote:
>> On Thu, Nov 13, 2025, at 08:13, Joel Jacobson wrote:
>>> Attached, please find a new version rebased on top of the bug fix
>>> patches that just got committed in 0bdc777, 797e9ea, 8eeb4a0, and
>>> 1b46990.
>>
>> To help reviewers, here is a new write-up of the patch:
>> [...write-up...]
>
...
> The attached v28 is the same as v27, except some comments have been
> fixed to accurately reflect the code.

I note LISTEN/NOTIFY yet again made it to the front-page of Hacker News
due to complaints of being a bottleneck:

https://peterullrich.com/listen-to-database-changes-through-the-postgres-wal
https://news.ycombinator.com/item?id=45885768

Unfortunately, the article doesn't say if the workload in the example
is made up, or if it's based on actual numbers, and it doesn't say
if they listened to a single channel or multiple channels.

/Joel