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Postgres LISTEN/NOTIFY does not scale

(www.recall.ai)
570 points davidgu | 2 comments | 07 Jul 25 14:05 UTC | HN request time: 0.637s | source
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leontrolski ◴[10 Jul 25 21:00 UTC] No.44525560[source]▶
I'd be interested as to how dumb-ol' polling would compare here (the FOR UPDATE SKIP LOCKED method https://leontrolski.github.io/postgres-as-queue.html). One day I will set up some benchmarks as this is the kind of thing people argue about a lot without much evidence either way.

Wasn't aware of this AccessExclusiveLock behaviour - a reminder (and shameless plug 2) of how Postgres locks interact: https://leontrolski.github.io/pglockpy.html

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1. aurumque ◴[10 Jul 25 21:03 UTC] No.44525593[source]▶
I'll take the shameless plug. Thank you for putting this together! Very helpful overview of pg locks.
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2. notarobot123 ◴[11 Jul 25 18:08 UTC] No.44535273[source]▶
It's funny how "shameless plug" actually means "excuse the self-promotion" and implies at least a little bit of shame even when the reference is appropriate and on-topic.