Postgres FM

Nik and Michael are joined by Bruce Momjian to discuss his new talk "What’s Missing in Postgres?"
 
Here are some links to things they mentioned: 
Bruce Momjian https://postgres.fm/people/bruce-momjian
EDB https://www.enterprisedb.com
What’s Missing in Postgres? (Bruce’s slides) https://momjian.us/main/writings/pgsql/missing.pdf
The Wonderful World of WAL (Bruce’s slides) https://momjian.us/main/writings/pgsql/wal.pdf
Getting started with benchmarking (our episode with Melanie Plageman) https://postgres.fm/episodes/getting-started-with-benchmarking
Myths and Truths about Synchronous Replication in Postgres (talk by Alexander Kukushkin) https://www.youtube.com/watch?v=PFn9qRGzTMc
The Future of Postgres Sharding (Bruce’s slides) https://momjian.us/main/writings/pgsql/sharding.pdf
MultiXact member space exhaustion https://postgres.fm/episodes/multixact-member-space-exhaustion

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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!

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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

Nik and Michael discuss long-running transactions, including when they're harmless, when they cause issues, and how to mitigate those issues.
 
Here are some links to things they mentioned: 
transaction_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-TRANSACTION-TIMEOUT
Our episode on transaction_timeout https://postgres.fm/episodes/transaction_timeout
Our episode on slow queries (which was also our first ever episode!) https://postgres.fm/episodes/slow-queries-and-slow-transactions
Our episode on locks https://postgres.fm/episodes/locks
lock_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-LOCK-TIMEOUT
Transaction Isolation levels https://www.postgresql.org/docs/current/transaction-iso.html
pg_current_xact_id_if_assigned() https://pgpedia.info/p/pg_current_xact_id_if_assigned.html
Monitor xmin horizon to prevent XID/MultiXID wraparound and high bloat (how-to guide by Nik) https://postgres.ai/docs/postgres-howtos/performance-optimization/monitoring/how-to-monitor-xmin-horizon
idle_replication_slot_timeout https://www.postgresql.org/docs/current/runtime-config-replication.html#GUC-IDLE-REPLICATION-SLOT-TIMEOUT
PREPARE TRANSACTION https://www.postgresql.org/docs/current/sql-prepare-transaction.html
log_autovacuum_min_duration https://www.postgresql.org/docs/devel/runtime-config-logging.html#GUC-LOG-AUTOVACUUM-MIN-DURATION
PostgreSQL Subtransactions Considered Harmful (blog post by Nikolay) https://postgres.ai/blog/20210831-postgresql-subtransactions-considered-harmful
statement_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-STATEMENT-TIMEOUT
idle_in_transaction_session_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-IDLE-IN-TRANSACTION-SESSION-TIMEOUT
lock_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-LOCK-TIMEOUT

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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

Nik and Michael are joined by Regina Obe and Paul Ramsey to discuss PostGIS.
 
Here are some links to things they mentioned:
Regina Obe https://postgres.fm/people/regina-obe
Paul Ramsey https://postgres.fm/people/paul-ramsey
PostGIS https://postgis.net
MobilityDB https://github.com/MobilityDB/MobilityDB
pgRouting https://github.com/pgRouting/pgrouting
Google BigQuery GIS public alpha blog post https://cloud.google.com/blog/products/data-analytics/whats-happening-bigquery-integrated-machine-learning-maps-and-more
PostGIS Day 2025 talk recordings https://www.youtube.com/watch?v=wuNO_cW2g-0&list=PLavJpcg8cl1EkQWoCbczsOjFTe-SHg_8m
pg_lake https://github.com/Snowflake-Labs/pg_lake
GeoParquet https://geoparquet.org
ST_DWithin https://postgis.net/docs/ST_DWithin.html
Postgres JSONB Columns and TOAST: A Performance Guide https://www.snowflake.com/en/engineering-blog/postgres-jsonb-columns-and-toast
FOSS4G https://foss4g.org
OpenStreetMap https://www.openstreetmap.org
PgDay Boston https://2026.pgdayboston.org
SKILL.md file https://github.com/postgis/postgis/blob/68dde711039986b47eb62feda45bb24b13b0ea37/doc/SKILL.md
Production query plans without production data (blog post by Radim Marek) https://boringsql.com/posts/portable-stats
PostgreSQL: Up and Running, 4th Edition (by Regina Obe, Leo Hsu) https://www.oreilly.com/library/view/postgresql-up-and/9798341660885

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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

Nik and Michael discuss query plan flips in Postgres — what they are, some causes, mitigations, longer term solutions, and the recent outage at Clerk.
 
Here are some links to things they mentioned: 
Recent postmortem from Clerk https://clerk.com/blog/2026-02-19-system-outage-postmortem
The real cost of random I/O (blog post by Tomas Vondra) https://vondra.me/posts/the-real-cost-of-random-io
autovacuum_analyze_scale_factor https://www.postgresql.org/docs/current/runtime-config-vacuum.html#GUC-AUTOVACUUM-ANALYZE-SCALE-FACTOR
default_statistics_target https://www.postgresql.org/docs/current/runtime-config-query.html#GUC-DEFAULT-STATISTICS-TARGET
pg_hint_plan https://github.com/ossc-db/pg_hint_plan
Aurora PostgreSQL query plan management https://docs.aws.amazon.comAmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Optimize.Start.html
pg_stat_plans https://github.com/pganalyze/pg_stat_plans
pg_plan_alternatives https://jnidzwetzki.github.io/2026/03/04/pg-plan-alternatives.html
Waiting for Postgres 19: Better Planner Hints with Path Generation Strategies https://pganalyze.com/blog/5mins-postgres-19-better-planner-hints

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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

Nik and Michael discuss pg_ash — a new tool (not extension!) from Nik that samples and stores wait events from pg_stat_activity.
 
Here are some links to things they mentioned: 
pg_ash https://github.com/NikolayS/pg_ash
pg_wait_sampling https://github.com/postgrespro/pg_wait_sampling
Amazon RDS performance insights https://aws.amazon.com/rds/performance-insights
Our episode on wait events https://postgres.fm/episodes/wait-events
pg-flight-recorder https://github.com/dventimisupabase/pg-flight-recorder
pg_profile https://github.com/zubkov-andrei/pg_profile
pg_cron https://github.com/citusdata/pg_cron

~~~
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