Postgres FM

Locks

Postgres FM

Show Notes

Nikolay and Michael discuss heavyweight locks in Postgres — how to think about them, why you can't avoid them, and some tips for minimising issues.

Here are some links to things they mentioned: Locking (docs) https://www.postgresql.org/docs/current/explicit-locking.html Postgres rocks, except when it blocks (blog post by Marco Slot) https://www.citusdata.com/blog/2018/02/15/when-postgresql-blocks/ Lock Conflicts (tool by Hussein Nasser) https://pglocks.org/ log_lock_waits (docs) https://www.postgresql.org/docs/current/runtime-config-logging.html#GUC-LOG-LOCK-WAITS How to analyze heavyweight lock trees (guide by Nikolay) https://gitlab.com/postgres-ai/postgresql-consulting/postgres-howtos/-/blob/main/0042_how_to_analyze_heavyweight_locks_part_2.md Lock management (docs) https://www.postgresql.org/docs/current/runtime-config-locks.html Our episode on zero-downtime migrations https://postgres.fm/episodes/zero-downtime-migrations

~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc!

~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustard Nikolay Samokhvalov, founder of Postgres.ai

With credit to: Jessie Draws for the elephant artwork

More from Postgres FM

Oct 23, 2026

Nik is joined by Kirk Wolak, Software Architect at KiraSoft, to discuss what a database still needs after pg_restore finishes and before it takes production traffic — what pg_dump and pg_restore leave behind, why autovacuum may not catch up in time, and how Postgres itself could do better.

Oct 16, 2026

Nik and Michael are joined by Álvaro Hernández to discuss sharding Postgres with Citus and StackGres, especially the new query router support that has been added very recently.

Sep 25, 2026

Nik and Michael are joined by Salma El-Sayed and Kirk Wolak to discuss their in-progress and very ambitious Google Summer of Code project around adding Btree Merge support to Postgres.

Sep 18, 2026

Nik and Michael are joined by Sai Srirampur to discuss ClickHouse's new managed Postgres service.

Sep 11, 2026

Nik and Michael discuss hot_standby_feedback — what it controls, whether and when read replicas should be changed to on, and other settings you can change to help too.

See all episodes →