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postgres 19 has WAIT FOR LSN, which means you can finally drop the "sleep and hope" workarounds for reading your own writes from replicas. I did all the digging around. Sample Go implementation, and the Rails workaround (Active Record thinks WAIT FOR is a write 🙃) boringsql.com/posts/read-y...

boringsql.comRead your own writes, off the primaryWAIT FOR in PostgreSQL 19 lets a reader block until the replica has replayed a specific LSN. Measured against sticky routing, sleeps, and synchronous commit, on a replica that misses the write 99% of ...

1/9/26, 7:03 am1 repost2 likes

Radim @ boringSQL

@boringsql.com

1 Sept

@apatheticmagpie.bsky.social wrote the mechanics piece last week (seriously read hers first) she saved me from the boring part. what i did was stress-test it and measure what actually happens. clickhouse.com/blog/postgre...

clickhouse.comRead your writes: WAIT FOR in PostgreSQL 19 | ClickHousePostgreSQL 19's new `WAIT FOR` command enables read-your-writes consistency on asynchronous replicas by letting individual reads wait for a specific WAL position.

Radim @ boringSQL

@boringsql.com

1 Sept

For impatient here's TL;DR: even with replica on the same machine, loopback, naive reads miss 99.2% of the time. not sometimes. not under load. always.