Postgres FM

What’s Missing in Postgres?

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-momjianEDB https://www.enterprisedb.comWhat’s Missing in Postgres? (Bruce’s slides) https://momjian.us/main/writings/pgsql/missing.pdfThe Wonderful World of WAL (Bruce’s slides) https://momjian.us/main/writings/pgsql/wal.pdfGetting started with benchmarking (our episode with Melanie Plageman) https://postgres.fm/episodes/getting-started-with-benchmarkingMyths and Truths about Synchronous Replication in Postgres (talk by Alexander Kukushkin) https://www.youtube.com/watch?v=PFn9qRGzTMcThe Future of Postgres Sharding (Bruce’s slides) https://momjian.us/main/writings/pgsql/sharding.pdfMultiXact member space exhaustion https://postgres.fm/episodes/multixact-member-space-exhaustion~~~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 pgMustardNikolay Samokhvalov, founder of Postgres.aiWith credit to:Jessie Draws for the elephant artwork

Long-running transactions

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-TIMEOUTOur episode on transaction_timeout https://postgres.fm/episodes/transaction_timeoutOur episode on slow queries (which was also our first ever episode!) https://postgres.fm/episodes/slow-queries-and-slow-transactionsOur episode on locks https://postgres.fm/episodes/lockslock_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-LOCK-TIMEOUTTransaction Isolation levels https://www.postgresql.org/docs/current/transaction-iso.htmlpg_current_xact_id_if_assigned() https://pgpedia.info/p/pg_current_xact_id_if_assigned.htmlMonitor 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-horizonidle_replication_slot_timeout https://www.postgresql.org/docs/current/runtime-config-replication.html#GUC-IDLE-REPLICATION-SLOT-TIMEOUTPREPARE TRANSACTION https://www.postgresql.org/docs/current/sql-prepare-transaction.htmllog_autovacuum_min_duration https://www.postgresql.org/docs/devel/runtime-config-logging.html#GUC-LOG-AUTOVACUUM-MIN-DURATIONPostgreSQL Subtransactions Considered Harmful (blog post by Nikolay) https://postgres.ai/blog/20210831-postgresql-subtransactions-considered-harmfulstatement_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-STATEMENT-TIMEOUTidle_in_transaction_session_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-IDLE-IN-TRANSACTION-SESSION-TIMEOUTlock_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-LOCK-TIMEOUT~~~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 pgMustardNikolay Samokhvalov, founder of Postgres.aiWith credit to:Jessie Draws for the elephant artwork

PostGIS

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-obePaul Ramsey https://postgres.fm/people/paul-ramseyPostGIS https://postgis.netMobilityDB https://github.com/MobilityDB/MobilityDBpgRouting https://github.com/pgRouting/pgroutingGoogle BigQuery GIS public alpha blog post https://cloud.google.com/blog/products/data-analytics/whats-happening-bigquery-integrated-machine-learning-maps-and-morePostGIS Day 2025 talk recordings https://www.youtube.com/watch?v=wuNO_cW2g-0&list=PLavJpcg8cl1EkQWoCbczsOjFTe-SHg_8mpg_lake https://github.com/Snowflake-Labs/pg_lakeGeoParquet https://geoparquet.orgST_DWithin https://postgis.net/docs/ST_DWithin.htmlPostgres JSONB Columns and TOAST: A Performance Guide https://www.snowflake.com/en/engineering-blog/postgres-jsonb-columns-and-toastFOSS4G https://foss4g.orgOpenStreetMap https://www.openstreetmap.orgPgDay Boston https://2026.pgdayboston.orgSKILL.md file https://github.com/postgis/postgis/blob/68dde711039986b47eb62feda45bb24b13b0ea37/doc/SKILL.mdProduction query plans without production data (blog post by Radim Marek) https://boringsql.com/posts/portable-statsPostgreSQL: Up and Running, 4th Edition (by Regina Obe, Leo Hsu) https://www.oreilly.com/library/view/postgresql-up-and/9798341660885~~~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 pgMustardNikolay Samokhvalov, founder of Postgres.aiWith credit to:Jessie Draws for the elephant artwork

Plan flips

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-postmortemThe real cost of random I/O (blog post by Tomas Vondra) https://vondra.me/posts/the-real-cost-of-random-ioautovacuum_analyze_scale_factor https://www.postgresql.org/docs/current/runtime-config-vacuum.html#GUC-AUTOVACUUM-ANALYZE-SCALE-FACTORdefault_statistics_target https://www.postgresql.org/docs/current/runtime-config-query.html#GUC-DEFAULT-STATISTICS-TARGETpg_hint_plan https://github.com/ossc-db/pg_hint_planAurora PostgreSQL query plan management https://docs.aws.amazon.comAmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Optimize.Start.htmlpg_stat_plans https://github.com/pganalyze/pg_stat_planspg_plan_alternatives https://jnidzwetzki.github.io/2026/03/04/pg-plan-alternatives.htmlWaiting for Postgres 19: Better Planner Hints with Path Generation Strategies https://pganalyze.com/blog/5mins-postgres-19-better-planner-hints~~~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 pgMustardNikolay Samokhvalov, founder of Postgres.aiWith credit to:Jessie Draws for the elephant artwork

pg_ash

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_ashpg_wait_sampling https://github.com/postgrespro/pg_wait_samplingAmazon RDS performance insights https://aws.amazon.com/rds/performance-insightsOur episode on wait events https://postgres.fm/episodes/wait-eventspg-flight-recorder https://github.com/dventimisupabase/pg-flight-recorderpg_profile https://github.com/zubkov-andrei/pg_profilepg_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 pgMustardNikolay Samokhvalov, founder of Postgres.aiWith credit to:Jessie Draws for the elephant artwork