Nikolay and Michael discuss a common question — why Postgres isn't using an index, and what you can do about it! Here are some links to things they mentioned:Why isn’t Postgres using my index? (blog post by Michael) https://www.pgmustard.com/blog/why-isnt-postgres-using-my-index Why isn’t Postgres using my functional index? (Stack Exchange question from Brent Ozar) https://dba.stackexchange.com/questions/336019/why-isnt-postgres-using-my-functional-index enable_seqscan (and similar parameters) https://www.postgresql.org/docs/current/runtime-config-query.html Crunchy Bridge changed random_page_cost to 1.1 https://docs.crunchybridge.com/changelog#postgres_random_page_cost_1_1 Make indexes invisible (trick from Haki Benita) https://hakibenita.com/sql-tricks-application-dba#make-indexes-invisible ANALYZE https://www.postgresql.org/docs/current/sql-analyze.htmlStatistics used by the planner https://www.postgresql.org/docs/current/planner-stats.html Our episode on query hints https://postgres.fm/episodes/query-hints transaction_timeout (commit for Postgres 17) https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=51efe38cb92f4b15b68811bcce9ab878fbc71ea5 What’s new in the Postgres 16 query planner / optimizer (blog post by David Rowley) https://www.citusdata.com/blog/2024/02/08/whats-new-in-postgres-16-query-planner-optimizer/ ~~~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 brought to you by:Nikolay Samokhvalov, founder of Postgres.aiMichael Christofides, founder of pgMustardWith special thanks to:Jessie Draws for the amazing artwork
2/23/2024 • 35 minutes, 25 seconds
Overhead of pg_stat_statements and pg_stat_kcache
Nikolay and Michael discuss the overhead of pg_stat_statements and pg_stat_kcache — mostly focusing on some interesting things Nikolay found while stress-testing some large spot instances up to and beyond 2m TPS(!) Here are some links to things they mentioned:pg_stat_statements https://www.postgresql.org/docs/current/pgstatstatements.htmlpg_stat_kcache https://github.com/powa-team/pg_stat_kcachepg_stat_statements overhead estimate in pganalyze FAQs https://pganalyze.com/faqWhat is the performance impact of pg_stat_statements? (DBA Stack Exchange answer with several links) https://dba.stackexchange.com/questions/303503/what-is-the-performance-impact-of-pg-stat-statementsTowards Millions TPS (blog post by Alexander Korotkov) https://akorotkov.github.io/blog/2016/05/09/scalability-towards-millions-tpsPostgres.ai blog post with links to benchmarks https://postgres.ai/blog/20240127-postges-ai-botpostgresql_cluster https://github.com/vitabaks/postgresql_clusterpg_wait_sampling https://github.com/postgrespro/pg_wait_samplingpg_stat_kcache issue, discussion, and fast resolution https://github.com/powa-team/pg_stat_kcache/issues/41 log_statement_sample_rate https://postgresqlco.nf/doc/en/param/log_statement_sample_rate/ auto_explain.sample_rate https://www.postgresql.org/docs/current/auto-explain.html#id-1.11.7.14.5.3.13.1.3pg_stat_statements performance penalty on Intel much higher than on AMD https://gitlab.com/postgres-ai/postgresql-consulting/tests-and-benchmarks/-/issues/52~~~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 brought to you by:Nikolay Samokhvalov, founder of Postgres.aiMichael Christofides, founder of pgMustardWith special thanks to:Jessie Draws for the amazing artwork
2/16/2024 • 34 minutes, 7 seconds
Modern SQL
Michael is joined by Markus Winand, creator of use-the-index-luke.com and modern-sql.com, and author of SQL Performance Explained, to discuss Modern SQL — what Markus means by it, why it's important, some benefits, some examples, and at least one phrase that should be on a t-shirt. Here are some links to things they mentioned:Modern SQL (site) https://modern-sql.comUse the index, Luke! (site) https://use-the-index-luke.comSQL Performance Explained (book) https://sql-performance-explained.comOur episode on NULLs https://postgres.fm/episodes/nulls-the-good-the-bad-the-ugly-and-the-unknownIS DISTINCT FROM (null-safe not equals comparison) https://modern-sql.com/caniuse/is-distinct-fromUNIQUE NULLS DISTINCT https://modern-sql.com/caniuse/unique-nulls-distinctModernes SQL ist mehr als SELECT * FROM (a German language podcast Markus was on recently) https://engineeringkiosk.dev/podcast/episode/99-modernes-sql-ist-mehr-als-select-from-mit-markus-winandMarkus’ website https://winand.at~~~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 special thanks to:Jessie Draws for the elephant artwork
2/2/2024 • 32 minutes, 9 seconds
Bloat
Michael is joined by Chelsea Dole, Staff Software Engineer and Tech Lead of the Data Storage Team at Brex, to discuss bloat. They cover what it is, why it's a problem, strategies for minimising it, and the options when it's really bad. Here are some links to things they mentioned:Managing your tuple graveyard (talk by Chelsea) https://www.youtube.com/watch?v=gAgbzvGT6ckpgstattuple https://www.postgresql.org/docs/current/pgstattuple.html pg_class https://www.postgresql.org/docs/current/catalog-pg-class.html Bloat in PostgreSQL: a taxonomy (talk by Peter Geoghegan) https://youtube.com/watch?v=JDG4bMHxCH8 It's Not You, It's Me: Breaking Up with Massive Tables via Partitioning (talk by Chelsea) https://youtube.com/watch?v=TafwSuLNxe8 pg_repack https://github.com/reorg/pg_repackpg_squeeze https://github.com/cybertec-postgresql/pg_squeeze VACUUM https://www.postgresql.org/docs/current/sql-vacuum.htmlautovacuum https://www.postgresql.org/docs/current/runtime-config-autovacuum.html CLUSTER https://www.postgresql.org/docs/current/sql-cluster.html HOT updates https://www.postgresql.org/docs/current/storage-hot.html Our episode on BUFFERS https://postgres.fm/episodes/buffers-by-default Our episode on TOAST https://postgres.fm/episodes/toast Our episode on index maintenance https://postgres.fm/episodes/index-maintenance Chelsea's website: https://chelseadole.com/~~~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 special thanks to:Jessie Draws for the amazing artwork
1/26/2024 • 36 minutes, 17 seconds
pgvector
Michael is joined by Jonathan Katz, PostgreSQL Core Team member, Principle Product Manager at AWS, and also pgvector contributor, to discuss pgvector. They cover what it is, why it's so popular all of a sudden, some tuning and tradeoff guidance, and a look to the future. Here are some links to things they mentioned:pgvector https://github.com/pgvector/pgvectorOur episode on companion databases https://postgres.fm/episodes/companion-databasesVectors are the new JSON (talk by Jonathan) https://www.youtube.com/watch?v=D_1zunKblAUpgvector 0.5.0 feature highlights and howtos (blog post by Jonathan) https://jkatz05.com/post/postgres/pgvector-overview-0.5.0HNSW indexing and searching (blog post by Jonathan) https://aws.amazon.com/blogs/database/accelerate-hnsw-indexing-and-searching-with-pgvector-on-amazon-aurora-postgresql-compatible-edition-and-amazon-rds-for-postgresqlOur episode on TOAST https://postgres.fm/episodes/toastpgvector changelog https://github.com/pgvector/pgvector/blob/master/CHANGELOG.mdHQANN paper https://arxiv.org/abs/2207.07940HNSW fast build branch https://github.com/pgvector/pgvector/tree/hnsw-fast-build pgconf.dev https://2024.pgconf.dev ~~~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 special thanks to:Jessie Draws for the amazing artwork
1/19/2024 • 49 minutes, 6 seconds
pgBadger
Michael is joined by Alicja Kucharczyk, Program Manager for Azure Database for PostgreSQL at Microsoft and organiser of the Warsaw PostgreSQL User Group, to discuss Alicja's favorite tool: pgBadger. They cover what it is, how and when it's useful, and some guidance for getting the most out of it (without causing an outage). Here are some links to things they mentioned:pgBadger website https://pgbadger.darold.net pgBadger repo https://github.com/darold/pgbadgerAn example pgBadger report https://pgbadger.darold.net/examples/sample.html pg_stat_statements https://www.postgresql.org/docs/current/pgstatstatements.htmlAzure Guide https://techcommunity.microsoft.com/t5/azure-database-for-postgresql/how-to-generate-pgbadger-report-from-azure-database-for/ba-p/3756328Google Cloud SQL guide https://cloud.google.com/blog/products/databases/guide-to-the-database-observability-with-cloud-sqlRDS guide https://aws.amazon.com/blogs/database/optimizing-and-tuning-queries-in-amazon-rds-postgresql-based-on-native-and-external-tools/Community Insights on pgBadger (PGSQL Phriday Recap) https://techcommunity.microsoft.com/t5/azure-database-for-postgresql/community-insights-on-pgbadger-a-pgsql-phriday-010-recap/ba-p/3880911 PGSQL Phriday #010: Log analysis (blog post by Lætitia Avrot) https://mydbanotebook.org/post/log-analysis/ Nothing Compares To VACUUM/The Ballad of Bloat https://www.youtube.com/watch?v=2NxIngqq1y0 Explain Analyze (Feliz Navidad cover) https://www.youtube.com/watch?v=qznnzYZPdkM ~~~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 special thanks to:Jessie Draws for the amazing artwork
1/12/2024 • 31 minutes, 31 seconds
EXPLAIN
With Nikolay taking a well-earned break, Michael covers the basics of EXPLAIN — what it is, the parameters available, and a process he recommends for using it. Here are some links to the things mentioned:EXPLAIN (docs) https://www.postgresql.org/docs/current/sql-explain.htmlUsing EXPLAIN (docs) https://www.postgresql.org/docs/current/using-explain.html EXPLAIN Explained (talk by Josh Berkus https://www.youtube.com/watch?app=desktop&v=mCwwFAl1pBU Beyond joins and indexes (slides from talk by Bruce Momjian) https://momjian.us/main/writings/pgsql/beyond.pdf Depesz https://explain.depesz.com Dalibo https://explain.dalibo.com pgMustard https://www.pgmustard.com/ A beginners guide to explain (talk by Michael) https://www.youtube.com/watch?v=31EmOKBP1PY&t=24s Explain beyond the basics (talk by Michael) https://www.youtube.com/watch?v=sGkSOvuaPs4 auto_explain episode https://postgres.fm/episodes/auto_explain Row estimates episode https://postgres.fm/episodes/row-estimates Slow queries and slow transactions episode https://postgres.fm/episodes/slow-queries-and-slow-transactionsBenchmarking episode https://postgres.fm/episodes/benchmarking EXPLAIN glossary by Michael (forgot to mention, oops!) https://www.pgmustard.com/docs/explain ~~~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 brought to you by:Nikolay Samokhvalov, founder of Postgres.aiMichael Christofides, founder of pgMustardWith special thanks to:Jessie Draws for the amazing artwork
1/5/2024 • 19 minutes, 33 seconds
work_mem
Happy holidays! Today's topic is work_mem — how it's used and how to tune it.Related post: https://x.com/samokhvalov/status/1740813478150189172?s=46&t=HSxrW86NZqzPQP9vXVJEWg.
12/31/2023 • 19 minutes, 7 seconds
Partitioning by ULID
Nikolay and Michael discuss partitioning by ULID — revisiting some of the old UUID vs bigint key debate in light of some new UUID specs, and how these can be used for partitioning (by time). Here are some links to things they mentioned:
Nikolay’s episode on UUID (for primary keys) https://postgres.fm/episodes/uuid
Postgres TV hacking session with Andrey and Kirk: https://www.youtube.com/watch?v=YPq_hiOE-N8
UUIDv7 patch https://commitfest.postgresql.org/43/4388/
Use ULID Idempotency Keys (tip 6 in this blog post from Shopify) https://shopify.engineering/building-resilient-payment-systems
Nikolay’s howto post on UUID v7 and partitioning with TimescaleDB https://gitlab.com/postgres-ai/postgresql-consulting/postgres-howtos/-/blob/main/0065_uuid_v7_and_partitioning_timescaledb.md
Hussein Nasser’s YouTube video about the above https://www.youtube.com/watch?v=f53-Iw_5ucA
UUID proposal that includes UUIDv7 and UUIDv8 (work in progress): https://datatracker.ietf.org/doc/draft-ietf-uuidrev-rfc4122bis/history/
James Blackwood-Sewell advice on more elegant solution using TimescaleDB https://twitter.com/jamessewell/status/1730125437903450129
ULIDs and Stripe IDs (section of Identity Crisis blog post by Brandur) https://brandur.org/nanoglyphs/026-ids#ulids
Crunchy Bridge changed their default random_page_cost to 1.1 🙌 https://twitter.com/brandur/status/1720477470116422028
UUIDs vs serials for keys (newer post from Christophe Pettus) https://thebuild.com/blog/2023/02/16/uuids-vs-serials-for-keys/
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/22/2023 • 38 minutes, 53 seconds
Hash indexes
Nikolay and Michael discuss hash indexes in Postgres — what they are, some brief history, their pros and cons vs btrees, and whether or when they recommend using them. Here are some links to things they mentioned:
Index types (docs) https://www.postgresql.org/docs/current/indexes-types.html
Re-introducing hash indexes in PostgreSQL (blog post by Haki Benita and Michael) https://hakibenita.com/postgresql-hash-index
Hash indexes intro (docs) https://www.postgresql.org/docs/current/hash-intro.html
Hash indexes implementation (docs) https://www.postgresql.org/docs/current/hash-implementation.html
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/15/2023 • 30 minutes, 32 seconds
Constraints
Nikolay and Michael discuss PostgreSQL constraints — the six different types we have, how to add and modify them, including on large tables with high TPS. Here are some links to things they mentioned:
Constraints (docs) https://www.postgresql.org/docs/current/ddl-constraints.html
Unique index vs unique constraint issue (2017) https://www.postgresql.org/message-id/flat/CANNMO%2B%2B7%2BuVMj%2BZPGKB_zuRpKE0sNthy2Z-_oKSS%3DoE3_rN7QA%40mail.gmail.com
Our episode on NULLs https://postgres.fm/episodes/nulls-the-good-the-bad-the-ugly-and-the-unknown
Advanced Int to Bigint Conversions (talk by Robert Treat) https://www.youtube.com/watch?v=_IieyXzdmcM
Use BIGINT in Postgres (blog post by Ryan Lambert) https://blog.rustprooflabs.com/2021/06/postgres-bigint-by-default
How to add a foreign key (Tweet by Nikolay) https://twitter.com/samokhvalov/status/1732056107483636188
Bloat, pg_repack, and deferred constraints (blog post by Nikolai Averin from Miro) https://medium.com/miro-engineering/postgresql-bloat-pg-repack-and-deferred-constraints-d0ecf33337ec
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/8/2023 • 39 minutes, 4 seconds
Events
Nikolay and Michael discuss PostgreSQL events — whether in-person or online, large conferences or small meet-ups, as well as some strong opinions based on their experiences attending, speaking, and organising them. Here are some links to things they mentioned:
PGSQL Phriday #014: PostgreSQL Events https://www.cybertec-postgresql.com/en/pgsql-phriday-014-postgresql-events/
PGCon https://www.pgcon.org/
Highload https://highload.rs/
The San Francisco Bay Area PostgreSQL Meetup Group https://www.meetup.com/postgresql-1/
Our episode on “Why is Postgres popular?” https://postgres.fm/episodes/why-is-postgres-popular
PGConf EU https://pgconf.eu/
Open talks series on Postgres TV https://www.youtube.com/playlist?list=PLH8y1BNPAKjJCuZiDRl0qUEDaKLBpFvZ9
Rails World (including videos!) https://rubyonrails.org/world
Upcoming events https://www.postgresql.org/about/events/
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/1/2023 • 52 minutes, 9 seconds
Subtransactions
Nikolay and Michael discuss PostgreSQL subtransactions — what they are, and four issues they can cause at scale. Here are some links to things they mentioned:
Subtransactions (docs) https://www.postgresql.org/docs/current/subxacts.html
SAVEPOINT (docs) https://www.postgresql.org/docs/current/sql-savepoint.html
PostgreSQL Subtransactions Considered Harmful (blog post by Nikolay) https://postgres.ai/blog/20210831-postgresql-subtransactions-considered-harmful
Subtransactions and performance in PostgreSQL (blog post by Laurenz at Cybertec) https://www.cybertec-postgresql.com/en/subtransactions-and-performance-in-postgresql/
Notes on some PostgreSQL implementation details (blog post by Nelson Elhage) https://buttondown.email/nelhage/archive/notes-on-some-postgresql-implementation-details/
Why we spent the last month eliminating PostgreSQL subtransactions (GitLab blog post) https://about.gitlab.com/blog/2021/09/29/why-we-spent-the-last-month-eliminating-postgresql-subtransactions/
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/24/2023 • 24 minutes, 12 seconds
Companion databases
Nikolay and Michael discuss companion databases — when and why you might want to add another database management system to your stack (or not), and some specifics for analytics, timeseries, search, and vectors. Here are some links to things they mentioned:
Heap were using Postgres + Citus for analytics as of 2022 https://www.heap.io/blog/juggling-state-machines-incident-response-and-data-soup-a-glimpse-into-heaps-engineering-culture
Heap recently moved their core analytics to SingleStore (we only spotted this after recording 🤦♂️) https://www.heap.io/blog/heaps-next-generation-data-platform
Posthog moved their analytics from Postgres to Clickhouse https://posthog.com/blog/clickhouse-vs-postgres
Timescale https://www.timescale.com/
Citus https://www.citusdata.com/
Hydra https://www.hydra.so/
Our episode on real-time analytics https://postgres.fm/episodes/real-time-analytics
Our episode on queues https://postgres.fm/episodes/queues-in-postgres
Our episode on logical replication https://postgres.fm/episodes/logical-replication
Full Text Search in PostgreSQL (docs) https://www.postgresql.org/docs/current/textsearch.html
ZomboDB https://www.zombodb.com/
ParadeDB https://www.paradedb.com/
PeerDB https://www.peerdb.io/
RUM indexes https://github.com/postgrespro/rum
Debezium https://debezium.io/
pgmq https://github.com/tembo-io/pgmq
Tembo https://tembo.io/
pgvector vs Pinecone (Supabase blog post) https://supabase.com/blog/pgvector-vs-pinecone
Jepsen analyses https://jepsen.io/analyses
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/17/2023 • 45 minutes, 58 seconds
Blue-green deployments
Nikolay and Michael discuss blue-green deployments — specifically an RDS blog post, how similar this is (or not) to what they understand to be blue-green deployments, and how applicable the methodology might be in the database world more generally. Here are some links to things they mentioned:
Fully managed Blue/Green Deployment in Amazon Aurora PostgreSQL and Amazon RDS for PostgreSQL https://aws.amazon.com/blogs/database/new-fully-managed-blue-green-deployment-in-amazon-aurora-postgresql-and-amazon-rds-for-postgresql/
Blue-green deployment (blog post by Martin Fowler) https://martinfowler.com/bliki/BlueGreenDeployment.html
Our episode on logical replication https://postgres.fm/episodes/logical-replication
pgroll https://github.com/xataio/pgroll
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/10/2023 • 43 minutes, 45 seconds
Data model trade-offs
Nikolay and Michael discuss data model trade-offs — some cases where you might want to (gasp) de-normalize, and which PostgreSQL internals are at play. Here are some links to things they mentioned:
Our episode on JSON https://postgres.fm/episodes/json
PostgreSQL limits https://www.postgresql.org/docs/current/limits.html
Boyce–Codd normal form https://en.wikipedia.org/wiki/Boyce–Codd_normal_form
Our episode on over-indexing https://postgres.fm/episodes/over-indexing
Heap-Only Tuples (HOT) optimisation https://www.postgresql.org/docs/current/storage-hot.html
The Surprising Impact of Medium-Size Texts on PostgreSQL Performance https://hakibenita.com/sql-medium-text-performance
Query planner settings (collapse limits and Genetic Query Optimizer) https://www.postgresql.org/docs/current/runtime-config-query.html
WITH Queries (Common Table Expressions) https://www.postgresql.org/docs/current/queries-with.html
Our episode on benchmarking https://postgres.fm/episodes/benchmarking
The tests and benchmarks Nikolay mentioned https://gitlab.com/postgres-ai/postgresql-consulting/tests-and-benchmarks/-/issues
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/3/2023 • 38 minutes, 4 seconds
Under-indexing
Nikolay and Michael discuss under-indexing — how to tell if this applies to you, some general and specific cases, as well as some tricky ones. Here are some links to things they mentioned:
Indexes (docs) https://www.postgresql.org/docs/current/indexes.html
random_page_cost https://postgresqlco.nf/doc/en/param/random_page_cost/
Sequential scans https://www.pgmustard.com/docs/explain/sequential-scan
pg_stat_user_tables https://pgpedia.info/p/pg_stat_user_tables.html
pg_stat_statements https://www.postgresql.org/docs/current/pgstatstatements.html
auto_explain https://www.postgresql.org/docs/current/auto-explain.html
Our episode on slow queries https://postgres.fm/episodes/slow-queries-and-slow-transactions
Our episode on query macro analysis https://postgres.fm/episodes/macro-query-analysis-intro
Running 10 Million PostgreSQL Indexes In Production (And Counting) https://www.heap.io/blog/running-10-million-postgresql-indexes-in-production
Faceting large result sets in PostgreSQL https://www.cybertec-postgresql.com/en/faceting-large-result-sets/
Our episode on over-indexing https://postgres.fm/episodes/over-indexing
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/27/2023 • 34 minutes, 36 seconds
Over-indexing
Nikolay and Michael discuss over-indexing — what we mean by it, the regular issues people discuss about it, as well as a novel one Nikolay has come across and benchmarked recently. Here are some links to things they mentioned:
Nikolay’s tweet on over-indexing https://twitter.com/samokhvalov/status/1713101666629927112
Heap-Only Tuples (HOT) optimization https://www.postgresql.org/docs/current/storage-hot.html
Our episode on index maintenance https://postgres.fm/episodes/index-maintenance
PgBouncer now supports prepared statements https://github.com/pgbouncer/pgbouncer/releases/tag/pgbouncer_1_21_0
Our episode on connection poolers https://postgres.fm/episodes/connection-poolers
Configurable FP_LOCK_SLOTS_PER_BACKEND (Hackers mailing list discussion) https://www.postgresql.org/message-id/flat/CAM527d-uDn5osa6QPKxHAC6srOfBH3M8iXUM%3DewqHV6n%3Dw1u8Q%40mail.gmail.com
LWLock:lock_manager (Amazon RDS docs) https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/wait-event.lw-lock-manager.html
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/20/2023 • 42 minutes, 45 seconds
Query hints
Nikolay and Michael discuss query hints — what they are, what we do and don't have in PostgreSQL, and some other things in and around the ecosystem to be aware of. Here are some links to some extra things they mentioned:
Query planning (docs) https://www.postgresql.org/docs/current/runtime-config-query.html
Statistics used by the planner (docs) https://www.postgresql.org/docs/current/planner-stats.html
default_statistics_target https://www.postgresql.org/docs/current/runtime-config-query.html#GUC-DEFAULT-STATISTICS-TARGET
Optimiser hints discussion (wiki) https://wiki.postgresql.org/wiki/OptimizerHintsDiscussion
An example mailing list thread from 2006 https://www.postgresql.org/message-id/flat/20061012151439.GT28647%40nasby.net
Peter Geoghegan tweet regarding invalid index https://twitter.com/petervgeoghegan/status/1599191964045672449
plantuner http://sigaev.ru/git/gitweb.cgi?p=plantuner.git;a=blob;hb=HEAD;f=README.plantuner
pg_hint_plan https://github.com/ossc-db/pg_hint_plan
Aurora PostgreSQL query plan management https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Optimize.overview.html
Building automatic adviser & performance tuning tools - Julien Rouhaud & Tatsuro Yamada: PGCon 2020 (the completely misremembered presentation Michael mentioned 🙈) https://www.youtube.com/watch?v=LQZK6p3SwwA
hypopg https://github.com/HypoPG/hypopg
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/13/2023 • 35 minutes, 38 seconds
Stop and start Postgres faster
In this episode (recorded live on YouTube), Nikolay discusses Postgres shutdown and startup times – how to troubleshoot them and, when needed, optimize. Some extra things mentioned in this episode:
#PostgresMarathon series – every day, Nikolay posts a new howto-style article https://twitter.com/hashtag/PostgresMarathon
Day 2: Postgres shutdown and restart attempts https://twitter.com/samokhvalov/status/1707147450044297673
Day 3: How to troubleshoot long Postgres startup https://twitter.com/samokhvalov/status/1707466169245171773
GitLab repo with #PostgresMarathon posts (markdown): https://gitlab.com/postgres-ai/postgresql-consulting/postgres-howtos
Episode 010 "WAL and checkpoint tuning": https://postgres.fm/episodes/wal-and-checkpoint-tuning
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/7/2023 • 29 minutes, 57 seconds
Backups
Nikolay and Michael discuss Postgres backups — why we need them, what the options are, whether a dump is a backup or not, and some considerations for lowering RPO and RTO at scale. Here are some links to some extra things they mentioned:
pg_dump https://www.postgresql.org/docs/current/app-pgdump.html
pg_basebackup https://www.postgresql.org/docs/current/app-pgbasebackup.html
pgBackRest https://github.com/pgbackrest/pgbackrest
WAL-G https://github.com/wal-g/wal-g
Barman https://github.com/EnterpriseDB/barman
Data loss at GitLab (2017) https://about.gitlab.com/blog/2017/02/01/gitlab-dot-com-database-incident/
Dev Deletes Entire Production Database, Chaos Ensues (YouTube video) https://www.youtube.com/watch?v=tLdRBsuvVKc
Our episode on corruption https://postgres.fm/episodes/corruption
DBLab Engine https://github.com/postgres-ai/database-lab-engine
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/29/2023 • 43 minutes, 4 seconds
Postgres 16
Nikolay and Michael discuss the release of PostgreSQL 16 — the most important new features, what they mean for us as users, whether and when to upgrade, and more. Here are some links to some extra things they mentioned:
Release notes https://www.postgresql.org/docs/current/release-16.html
New Features With Examples (PDF from Noriyoshi Shinoda of Hewlett Packard Enterprise Japan) https://h50146.www5.hpe.com/products/software/oe/linux/mainstream/support/lcc/pdf/PostgreSQL16Beta1_New_Features_en_20230528_1.pdf
Why Upgrade? (site by depesz) https://why-upgrade.depesz.com/
Waiting for PostgreSQL 16 (blog post series from Depesz) https://www.depesz.com/tag/pg16/
Our episode on favourite features https://postgres.fm/episodes/our-favourite-v16-feature
Our episode on logical replication https://postgres.fm/episodes/logical-replication
Active Active in Postgres 16 (blog post from Crunchy Data) https://www.crunchydata.com/blog/active-active-postgres-16
AlloyDB adaptive autovacuum https://cloud.google.com/blog/products/databases/alloydb-for-postgresql-under-the-hood-adaptive-autovacuum
Visualizing Postgres I/O Performance (talk by Melanie Plageman at PGCon) https://www.youtube.com/watch?v=CxyPZHG5beI
Our monitoring checklist episode https://postgres.fm/episodes/monitoring-checklist
pgvector https://github.com/pgvector/pgvector
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/22/2023 • 39 minutes, 35 seconds
Logical replication
Nikolay and Michael discuss logical replication — some history, initialization, change data capture, how to scale it, some limitiations, and ways that it is getting better. Here are some links to some things they mentioned:
Logical replication https://www.postgresql.org/docs/current/logical-replication.html
GitLab upgraded multi-terabyte, heavily-loaded clusters with zero-downtime https://twitter.com/samokhvalov/status/1700574156222505276
pg_waldump https://www.postgresql.org/docs/current/pgwaldump.html
pg_dump and external snapshots (blog post by Michael Paquier) https://paquier.xyz/postgresql-2/postgres-9-5-feature-highlight-pg-dump-snapshots/
Failover of logical replication slots in Patroni (talk by Alexander Kukushkin) https://www.youtube.com/watch?v=SllJsbPVaow
Our episode on replication https://postgres.fm/episodes/replication
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/15/2023 • 43 minutes, 1 second
Our favourite v16 feature
Nikolay and Michael discuss their favourite feature each from the upcoming PostgreSQL 16 release. Here are some links to some things they mentioned:
v16 draft release notes https://www.postgresql.org/docs/16/release-16.html
PGSQL Phriday #012 invitation from Ryan Booz https://www.pgsqlphriday.com/2023/08/pgsql-phriday-012/
Subscribe options for the podcast https://postgres.fm/subscribe
A recent closed source ClickHouse feature https://github.com/ClickHouse/ClickHouse/issues/44767#issuecomment-1683293218
Postgres TV hacking session with Andrey Borodin on \watch with limited number of loops (v16) https://www.youtube.com/watch?v=vTV8XhWf3mo
Allow \watch queries to stop on minimum rows returned (v17) https://github.com/postgres/postgres/commit/f347ec76e2a227e5c5b5065cce7adad16d58d209
pg_stat_io commit mentioning the op_bytes column (v16) https://github.com/postgres/postgres/commit/a9c70b46dbe152e094f137f7e6ba9cd3a638ee25
pg_size_pretty function https://www.postgresql.org/docs/current/functions-admin.html#id-1.5.8.33.9.3.2.2.7.1.1.1
Visualizing Postgres I/O Performance (talk by Melanie Plageman at PGCon) https://www.youtube.com/watch?v=CxyPZHG5beI
Our episode on BUFFERS https://postgres.fm/episodes/buffers-by-default
EXPLAIN (GENERIC_PLAN) blog post by Laurenz Albe https://www.cybertec-postgresql.com/en/explain-generic-plan-postgresql-16/
Running EXPLAIN on any query (video by Lukas Fittl) https://www.youtube.com/watch?v=CMftYJnqou0
PostgreSQL 16 Beta 1 New Features with Examples.(English Version) by Noriyoshi Shinoda https://twitter.com/nori_shinoda/status/1664481483355226114
Have auto_explain's log_verbose mode honor the value of compute_query_id (commitfest entry) https://commitfest.postgresql.org/42/4136/
Make auto_explain print the query identifier in verbose mode (commit) https://github.com/postgres/postgres/commit/9d2d9728b8d546434aade4f9667a59666588edd6
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/8/2023 • 27 minutes, 28 seconds
Connections
Nikolay and Michael discuss connections — the options, security and performance tradeoffs, and a few other things to be aware of. Here are some links to some things they mentioned:
Episode on connection poolers https://postgres.fm/episodes/connection-poolers
listen_addresses https://www.postgresql.org/docs/current/runtime-config-connection.html#GUC-LISTEN-ADDRESSES
SSLMODE Explained (blog post by Andrew Kane) https://ankane.org/postgres-sslmode-explained
pg_hba.conf https://www.postgresql.org/docs/current/auth-pg-hba-conf.html
Timing a query (blog post by Bruce Momjian) https://momjian.us/main/blogs/pgblog/2012.html#June_6_2012
How to connect (blog post by Lætitia Avrot) https://mydbanotebook.org/post/cant-connect/
Improving Postgres Connection Scalability: Snapshots (blog post by Andres Freund) https://techcommunity.microsoft.com/t5/azure-database-for-postgresql/improving-postgres-connection-scalability-snapshots/ba-p/1806462
idle_session_timeout https://www.postgresql.org/docs/current/runtime-config-client.html#GUC-IDLE-SESSION-TIMEOUT
Do you vacuum everyday? (talk by Hannu Krosing) https://www.youtube.com/watch?v=JcRi8Z7rkPg
Don’t use now() with pg_stat_activity (tweet by Nikolay) https://twitter.com/samokhvalov/status/1664981076014690304
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/1/2023 • 28 minutes, 20 seconds
Decoupled storage and compute
Nikolay and Michael discuss a listener question — about products that take Postgres and transform it to something that decouples compute from storage (RDS Aurora, GC AlloyDB, Neon etc.) and whether they see something like this landing upstream in the medium term.Here are some links to some things they mentioned:
Amazon Aurora https://aws.amazon.com/rds/aurora/
Google Cloud AlloyDB for PostgreSQL https://cloud.google.com/alloydb
Neon https://neon.tech/
Google Cloud Spanner https://cloud.google.com/spanner
Is Aurora PostgreSQL really faster and cheaper than RDS PostgreSQL? (blog post by Avinash Vallarapu from MigOps) https://www.migops.com/blog/is-aurora-postgresql-really-faster-and-cheaper-than-rds-postgresql-benchmarking/
Deep dive on Amazon Aurora with PostgreSQL compatibility (presentation by Grant McAllister) https://www.youtube.com/watch?v=HQg8wqlxefo
Intro to Aurora PostgreSQL Query Plan Management https://aws.amazon.com/blogs/database/introduction-to-aurora-postgresql-query-plan-management/
Michael Stonebraker Turing Award Lecture
Interview with Stas Kelvich from Neon on Postgres TV https://www.youtube.com/watch?v=4PUKNznq_eM
Interview with Ben Vandiver from Google Cloud Spanner on Postgres TV https://www.youtube.com/watch?v=BW-Uexhv-bk
Timescale Cloud bottomless storage feature (data tiering to Amazon S3) https://www.timescale.com/blog/expanding-the-boundaries-of-postgresql-announcing-a-bottomless-consumption-based-object-storage-layer-built-on-amazon-s3/
Testing Database Changes the Right Way (Heap Analytics article) https://www.heap.io/blog/testing-database-changes-right-way
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/25/2023 • 42 minutes, 33 seconds
Self-managing
Nikolay and Michael discuss self-managing Postgres — both the practicalities of doing so, as well as some managed-service style tooling. Here are some links to some things they mentioned:
Our episode on Managed services vs. DIY https://postgres.fm/episodes/managed-services-vs-diy
WAL-G https://github.com/wal-g/wal-g
pgBackRest https://pgbackrest.org/
Barman https://github.com/EnterpriseDB/barman
Dead Man’s Snitch https://deadmanssnitch.com/
Netdata https://www.netdata.cloud/
Upgrades https://postgres.fm/episodes/upgrades
High availability https://postgres.fm/episodes/high-availability
Configuration https://postgres.fm/episodes/default-configuration
Corruption https://postgres.fm/episodes/corruption
Connection poolers https://postgres.fm/episodes/connection-poolers
Index maintenance https://postgres.fm/episodes/index-maintenance
StackGres supported extensions (Michael was wrong, it also has a timescale_tls extension!) https://stackgres.io/extensions/
postgresql_cluster https://github.com/vitabaks/postgresql_cluster
Supabase self-hosting https://supabase.com/docs/guides/self-hosting
Tembo https://github.com/tembo-io/tembo
Open source licenses, clouds, Postgres (Postgres TV discussion) https://www.youtube.com/watch?v=1rcbyIjA4gI&t=149s
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/18/2023 • 37 minutes, 4 seconds
Sharding
Nikolay and Michael discuss sharding Postgres — what it means, why and when it's needed, and the available options right now. Here are some links to some things they mentioned:
PGSQL Friday monthly blogging event https://www.pgsqlphriday.com/
Did “sharding” come from Ultima Online? https://news.ycombinator.com/item?id=23438399
Our episode on partitioning: https://postgres.fm/episodes/partitioning
Vitess https://vitess.io/
Citus https://www.citusdata.com/
Lessons learned from sharding Postgres (Notion 2021) https://www.notion.so/blog/sharding-postgres-at-notion
The Great Re-shard (Notion 2023) https://www.notion.so/blog/the-great-re-shard
The growing pains of database architecture (Figma 2023) https://www.figma.com/blog/how-figma-scaled-to-multiple-databases/
Timescale multi-node https://docs.timescale.com/self-hosted/latest/multinode-timescaledb/about-multinode/
PgCat https://github.com/postgresml/pgcat
SPQR https://github.com/pg-sharding/spqr
PL/Proxy https://plproxy.github.io/
Sharding GitLab by top-level namespace https://about.gitlab.com/handbook/engineering/development/enablement/data_stores/database/doc/root-namespace-sharding.html
Loose foreign keys (GitLab) https://docs.gitlab.com/ee/development/database/loose_foreign_keys.html
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/11/2023 • 39 minutes, 45 seconds
Data types
Nikolay and Michael discuss data types in PostgreSQL — including system types, choosing between types, types provided by extensions, and more. Here are some links to some things they mentioned:
Data Types (docs) https://www.postgresql.org/docs/current/datatype.html
10 tips for beginners https://postgres.ai/blog/20230722-10-postgres-tips-for-beginners
Tid Scan (explain glossary) https://www.pgmustard.com/docs/explain/tid-scan
Don’t do this (wiki) https://wiki.postgresql.org/wiki/Don't_Do_This
Boundless `text` and back again https://brandur.org/text
UUID episode https://postgres.fm/episodes/uuid
I use ENUM (30min talk by Boriss Mejías) https://archive.fosdem.org/2021/schedule/event/postgresql_i_use_enum_vindicating_the_underdog_of_data_types/
Peter Geoghegan tweet https://twitter.com/petervgeoghegan/status/1680275871905775616
JSON episode https://postgres.fm/episodes/json
pg_repack reorder columns discussion https://github.com/reorg/pg_repack/issues/101
Use bigint https://blog.rustprooflabs.com/2021/06/postgres-bigint-by-default
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/4/2023 • 37 minutes, 1 second
High availability
Nikolay and Michael discuss HA (high availability) — what it means, tools and techniques for maximising it, while going through some of the more common causes of downtime. Here are some links to some things they mentioned:
https://en.wikipedia.org/wiki/High_availability
https://postgres.fm/episodes/upgrades
https://github.com/shayonj/pg_easy_replicate/
pg_easy_replicate discussion on Hacker News https://news.ycombinator.com/item?id=36405761
https://postgres.fm/episodes/connection-poolers
https://www.postgresql.org/docs/current/libpq.html
Support load balancing in libpq (new feature in Postgres 16) https://commitfest.postgresql.org/42/3679/
target_session_attrs options for high availability and scaling (2021; a post by Laurenz Albe) https://www.cybertec-postgresql.com/en/new-target_session_attrs-settings-for-high-availability-and-scaling-in-postgresql-v14/
Postgres 10 highlight - read-write and read-only mode of libpq (2016, a post by Michael Paquier) https://paquier.xyz/postgresql-2/postgres-10-libpq-read-write/
Postgres 10 highlight - Quorum set of synchronous standbys (2017, a post by Michael Paquier) https://paquier.xyz/postgresql-2/postgres-10-quorum-sync/
https://github.com/zalando/patroni
https://postgres.fm/episodes/replication
https://blog.rustprooflabs.com/2021/06/postgres-bigint-by-default
Zero-downtime Postgres schema migrations need this: lock_timeout and retries (2021) https://postgres.ai/blog/20210923-zero-downtime-postgres-schema-migrations-lock-timeout-and-retries
A fix in Patroni to mitigate a very long shutdown attempt when archive_command has a lot of WALs to archive https://github.com/zalando/patroni/pull/2067
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
7/28/2023 • 40 minutes, 40 seconds
Beginner tips
Nikolay and Michael discuss 10 beginner tips Nikolay recently shared — they go into a bit more detail on each, and even disagree a little on one or two! Here are some links to some things they mentioned:
Nikolay’s tweet with all 10 tips: https://twitter.com/samokhvalov/status/1679953049899642880
Tip 1: tuples are physical versions of rows
Related episodes: https://postgres.fm/episodes/how-to-become-a-dba and https://postgres.fm/episodes/hot-updates
Tip 2: always use EXPLAIN (ANALYZE, BUFFERS)
Related episode: https://postgres.fm/episodes/buffers-by-default
Tip 3: throw away pgAdmin
Related episode: https://postgres.fm/episodes/psql-vs-guis
Tip 4: enable as much logging as you can afford
Related episode: https://postgres.fm/episodes/default-configuration
Tip 5: install pg_stat_statements
Related episodes: https://postgres.fm/episodes/pg_stat_statements and https://postgres.fm/episodes/auto_explain, and https://postgres.fm/episodes/macro-query-analysis-intro
Tip 6: run experiments on realistic data sets (use thin cloning and branching)
Related episode: https://postgres.fm/episodes/database-branching
Tip 7: make sure data checksums are enabled
Related episode: https://postgres.fm/episodes/corruption
Tip 8: tune autovacuum to run frequently and move faster
Related episode: https://postgres.fm/episodes/vacuum
Tip 9: query optimization will eventually be more important than configuration tuning
Related episodes: https://postgres.fm/episodes/intro-to-query-optimization and https://postgres.fm/episodes/102-query-optimization
Tip 10: indexes need to be rebuilt, unfortunately, since their health decline over time
Related episode: https://postgres.fm/episodes/index-maintenance
Bonus tip: the official documentation, release notes, and source code comments/readmes are your friends!
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
7/21/2023 • 40 minutes, 18 seconds
Connection poolers
Nikolay and Michael discuss Postgres connection poolers — when and why we need them, the king that is PgBouncer, and the many new pretenders to the throne. Here are links to a few things they mentioned:
max_connections https://www.postgresql.org/docs/current/runtime-config-connection.html#GUC-MAX-CONNECTIONS
Improving Postgres Connection Scalability: Snapshots (blog post by Andres Freund) https://techcommunity.microsoft.com/t5/azure-database-for-postgresql/improving-postgres-connection-scalability-snapshots/ba-p/1806462
PgBouncer https://github.com/pgbouncer/pgbouncer
Odyssey https://github.com/yandex/odyssey
PgCat https://github.com/postgresml/pgcat
Adopting PgCat: A Nextgen Postgres Proxy https://www.instacart.com/company/how-its-made/adopting-pgcat-a-nextgen-postgres-proxy/
Supavisor https://github.com/supabase/supavisor
pgagroal https://github.com/agroal/pgagroal
PgBouncer is useful, important, and fraught with peril (blog post from JP Camara) https://jpcamara.com/2023/04/12/pgbouncer-is-useful.html
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
7/14/2023 • 31 minutes, 29 seconds
Anniversary mailbag
Nikolay and Michael celebrate the podcast's 1 year anniversary by going through several questions and suggestions received over the year. Here are the questions and some links to things we mentioned:
Question 1: Effect of wal_log_hints=on after bulk Deletes: Why next select runs slow and generated tons of WAL? https://twitter.com/dmx551/status/1598253188926570496
wal_log_hints https://www.postgresql.org/docs/current/runtime-config-wal.html#GUC-WAL-LOG-HINTS
Exploring how SELECT Queries can produce disk writes https://blog.okmeter.io/postgresql-exploring-how-select-queries-can-produce-disk-writes-f36c8bee6b6f
Question 2: How to get started reading PostgreSQL source code. Maybe a PostgreSQL style C reference guide to consult with for non C programmers https://twitter.com/andatki/status/1578088843940593678
So, you want to be a developer? https://wiki.postgresql.org/wiki/So,_you_want_to_be_a_developer%3F
GitHub search https://github.com/search?q=repo%3Apostgres%2Fpostgres+wal_log_hints&type=code
The Internals of PostgreSQL (by Hironobu SUZUKI) https://www.interdb.jp/pg/
PostgreSQL 14 Internals (by Egor Rogov) https://postgrespro.com/community/books/internals
Question 3: Isolation Levels Primer/Strategies — their uses in different scenarios, battle tested strategies and insights, performance tradeoffs, edge cases to consider at scale (with replication and sharding, etc.) I remember reading some interesting stuff on the jepsen analysis https://jepsen.io/analyses/postgresql-12.3 about Postgres's Serializable Isolation Level behaving more like Snapshot Isolation. Has this type of behavior or another one similar to this affected you or your clients in any significant way?
Transaction Isolation https://www.postgresql.org/docs/current/transaction-iso.html
What developers find surprising about Postgres transactions https://blog.lawrencejones.dev/isolation-levels/
Question 4: Data encryption in Postgres
Cybertec Transparent Data Encryption https://www.cybertec-postgresql.com/en/products/postgresql-transparent-data-encryption/
EDB Transparent Data Encryption https://www.enterprisedb.com/docs/tde/latest/
Question 5: Migration from other DBMSs
PostgreSQL transition/migration guide https://github.com/postgresql-transition-guide/guide
Question 6: Latest failover best practices
Patroni https://github.com/zalando/patroni
~~~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 brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
7/7/2023 • 31 minutes, 24 seconds
pg_upgrade: the tricky and dangerous parts
Nikolay (alone, again) reveals some issues that might hit those who perform major PostgreSQL upgrades with minimal downtime.Links:- "Upgrades" – PostgresFM episode 037: https://postgres.fm/episodes/upgrades- recovery_target_lsn: https://postgresqlco.nf/doc/en/param/recovery_target_lsn/- recovery_target_action: https://postgresqlco.nf/doc/en/param/recovery_target_action/- pg_easy_replicate https://github.com/shayonj/pg_easy_replicate/- HN discussion of this tool: https://news.ycombinator.com/item?id=36405761- Waiting for Postgres 16: Logical decoding on standbys: https://pganalyze.com/blog/5mins-postgres-16-logical-decoding- pg_upgrade and logical replication (discussion in pgsql-hackers): https://www.postgresql.org/message-id/flat/20230217075433.u5mjly4d5cr4hcfe%40jrouhaud- allow upgrading publisher node (proposal to natively support running pg_upgrade on publisher, WIP): https://commitfest.postgresql.org/43/4273/- ❓🤔 pg_upgrade instructions involving "rsync --size-only" might lead to standby corruption? (discussion in pgsql-hackers): https://www.postgresql.org/message-id/flat/CAM527d8heqkjG5VrvjU3Xjsqxg41ufUyabD9QZccdAxnpbRH-Q%40mail.gmail.com~~~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!If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
6/30/2023 • 25 minutes, 38 seconds
UUID
Lonely Nikolay discusses the performance aspects of using UUID for primary keys. Here are links to a few things I mentioned:
"postgresql" posts on HN, most popular last week (Algolia search): https://hn.algolia.com/?dateRange=pastWeek&page=0&prefix=true&query=postgresql&sort=byPopularity&type=story
Unexpected downsides of UUID keys in PostgreSQL (a post by Ants Aasma, Cybertec): https://www.cybertec-postgresql.com/en/unexpected-downsides-of-uuid-keys-in-postgresql/
HN discussion of that post: https://news.ycombinator.com/item?id=36429986
Additional math by me (converting to bytes): https://twitter.com/samokhvalov/status/1671962111092850689
Updated RFC4122 (proposal): https://github.com/ietf-wg-uuidrev/rfc4122bis
Status of that proposal: https://datatracker.ietf.org/doc/draft-ietf-uuidrev-rfc4122bis/history/
Patch UUID v7 (commitfest record): https://commitfest.postgresql.org/43/4388/
Postgres hacking with Andrey and Kirk: https://www.youtube.com/watch?v=YPq_hiOE-N8 (where that patch was developed)
~~~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!If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
6/23/2023 • 22 minutes, 11 seconds
Memory
Nikolay and Michael discuss memory in PostgreSQL — how it works, important settings, and how to go about tuning them. Here are links to a few things we mentioned:
Resource Consumption (PostgreSQL docs) https://www.postgresql.org/docs/current/runtime-config-resource.html
Andres Freud tweet about shared_buffers https://twitter.com/AndresFreundTec/status/1438912583554113537
Henrietta (Hettie) Dombrovskaya https://hdombrovskaya.wordpress.com/about-the-author/
annotated.conf (by ash Berkus) https://github.com/jberkus/annotated.conf
Our episode about checkpoint tuning https://postgres.fm/episodes/wal-and-checkpoint-tuning
Our episode about BUFFERS https://postgres.fm/episodes/buffers-by-default
Analyzing the Limits of Connection Scalability in Postgres (blog post by Andres Freund) https://techcommunity.microsoft.com/t5/azure-database-for-postgresql/analyzing-the-limits-of-connection-scalability-in-postgres/ba-p/1757266#memory-usage
Tuning memory parameters for Aurora PostgreSQL https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.BestPractices.Tuning-memory-parameters.html
RDS for PostgreSQL memory https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/PostgreSQL.Tuning.concepts.html#PostgreSQL.Tuning.concepts.memory
EDB guide by Via Fearing https://www.enterprisedb.com/postgres-tutorials/introduction-postgresql-performance-tuning-and-optimization#resourceusage
pg_stat_kcache https://github.com/powa-team/pg_stat_kcache
pg_buffercache https://www.postgresql.org/docs/current/pgbuffercache.html
Process and Memory Architecture chapter (from Hironobu SUZUKI) https://www.interdb.jp/pg/pgsql02.html
PostgreSQL 14 internals PDF book from Egor Rogov (pages 37, 184) https://edu.postgrespro.com/postgresql_internals-14_en.pdf
src/backend/storage/buffer/README https://github.com/postgres/postgres/blob/master/src/backend/storage/buffer/README
pg_backend_memory_contexts (PostgreSQL 14+) https://www.postgresql.org/docs/current/view-pg-backend-memory-contexts.html
pg_stat_io (coming in PostgreSQL 16) https://www.postgresql.org/docs/devel/monitoring-stats.html#MONITORING-PG-STAT-IO-VIEW
pg_prewarm https://www.postgresql.org/docs/current/pgprewarm.html
Configuring work_mem blog post https://www.pgmustard.com/blog/work-mem
~~~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!If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
6/16/2023 • 44 minutes, 15 seconds
Extensions
Nikolay and Michael discuss Postgres extensions — what they are, how they affect your decisions around Postgres, and some things to keep in mind when using them. Here are links to a few things we mentioned:
Extensions (docs) https://www.postgresql.org/docs/current/external-extensions.html
Extension (pgPedia) https://pgpedia.info/e/extension.html
pgvector https://github.com/pgvector/pgvector
PL/Rust https://github.com/tcdi/plrust
ZomboDB https://github.com/zombodb/zombodb
Why is Postgres popular episode https://postgres.fm/episodes/why-is-postgres-popular
Citus https://github.com/citusdata/citus
TimescaleDB https://github.com/timescale/timescaledb
OrioleDB https://github.com/orioledb/orioledb
PostGIS https://trac.osgeo.org/postgis/
“There’s an extension for that” (tweet from Robert Treat) https://twitter.com/robtreat2/status/1665735485883314178
RDS supported extensions https://docs.aws.amazon.com/AmazonRDS/latest/PostgreSQLReleaseNotes/postgresql-extensions.html
RUM https://github.com/postgrespro/rum
pg_repack https://github.com/reorg/pg_repack
PGXN https://pgxn.org/
pgTrunk by CoreDB https://pgtrunk.io/
Dbdev by Supabase https://supabase.com/blog/dbdev
StackGres https://github.com/ongres/stackgres
pg_tle by AWS https://github.com/aws/pg_tle
Modern Postgres monitoring (slides from Nikolay’s tutorial) https://twitter.com/samokhvalov/status/1664686535562625034
Awesome Postgres https://github.com/dhamaniasad/awesome-postgres
~~~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!If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
6/9/2023 • 30 minutes, 23 seconds
Zero-downtime migrations
Nikolay and Michael discuss zero-downtime schema migrations — why they're a challenge, a variety of different cases, and some things you can do to achieve them. Here are links to a few things we mentioned:
Comparison of JOINS: MongoDB vs. PostgreSQL (blog post by Michael Stonebraker and Álvaro Hernández)
Common DB schema change mistakes (blog post by Nikolay)
lock_timeout and retries (blog post by Nikolay)
lock_timeout
Fast Column Creation with Defaults (blog post by Brandur)
Database Schema Changes Without Downtime (new version of blog post by Braintree)
Zero-downtime Postgres migrations - the hard parts (blog post from GoCardless)
GitLab migration_helpers.rb
GitLab migration style guide
dblab
~~~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!If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
6/2/2023 • 28 minutes, 8 seconds
Parallelism
Nikolay and Michael discuss parallelism — both parallel query execution and other parallel operations. Here are links to a few things we mentioned:
Parallel query (docs)
Parallelism in PostgreSQL 11 (talk by Thomas Munro)
Parallelism in PostgreSQL 15 (talk by Thomas Munro)
Towards Millions TPS (blog post by Alexander Korotkov)
Memory resource consumption (docs)
Our episode about index maintenance
Our episode about partitioning
Patch to make postgres_fdw parallel-safe (by Swarm64)
PostgreSQL Parallelism Do’s and Don’ts (talk by Sebastian Dressler)
Increasing max_parallel_workers_per_gather (blog post by Michael)
~~~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!If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
5/26/2023 • 44 minutes, 24 seconds
Corruption
Nikolay and Michael discuss database corruption — various types, how they can come about, and what to do (and not do) if you come across it. Here are links to a few things we mentioned:
The dangers of streaming across versions of glibc (TripAdvisor mailing list thread)
The floor is Java meme
Data Corruption talk by Sebastian Webber (on Postgres TV)
Data corruption monitoring & troubleshooting talk by Andrey Borodin (on Postgres TV)
Postgres data corruption (document from Nikolay)
Data Corruption and Bugs Runbook (document from Nikolay)
Corruption (Postgres wiki)
Checksums
pg_checksums
Original pg_checksums (by Credativ)
amcheck
Our episode on index maintenance
14.4 release notes about create index / reindex concurrently issue and fix
amcheck to check unique constraints in btree indexes (Commitfest entry)
amcheck verification of GiST and GIN (Commitfest entry)
How to corrupt your Postgres database (blog post from Cybertec)
Christophe Pettus talk
Christophe Pettus slides
pg_hexedit
pageinspect
pg_catcheck
~~~What did you like or not like? What should we discuss next time? Let us know on YouTube, on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
5/19/2023 • 42 minutes, 23 seconds
ChatGPT x PostgreSQL
Nikolay and Michael discuss using ChatGPT for Postgres tasks — should you, if so what for, and some things to be mindful of! Here are links to a few things we mentioned:
ChatGPT
Nikolay’s polls on Twitter and on LinkedIn
The Art of PostgreSQL (book by Dimitri Fontaine)
SQL Performance Explained (book by Markus Winand)
Nikolay’s YouTube correction about deletes and index amplification
Don’t use ChatGPT to solve problems (blog post by Christophe Pettus)
Query optimization session with ChatGPT, Michael, and Nikolay (on YouTube)
DBeaver SmartAssistance feature
Depesz anonymization feature
~~~What did you like or not like? What should we discuss next time? Let us know on YouTube, on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
5/12/2023 • 35 minutes, 1 second
pg_stat_statements
Nikolay and Michael discuss pg_stat_statements — why everyone should use it, but also some downsides! Here are links to a few things we mentioned:
pg_stat_statements (docs)
pg_stat_statements (PgPedia)
PGSQL Phriday
Observer effect in pg_stat_statements and pg_stat_kcache (Postgres Hacking session on Postgres TV)
track_io_timing (docs)
Overhead comment (by Tom Kate, via Jeremy Schneider)
pg_stat_monitor
PGCon
Our episode on query analysis
Marginalia
~~~What did you like or not like? What should we discuss next time? Let us know on YouTube, on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
5/5/2023 • 45 minutes, 51 seconds
auto_explain
Nikolay and Michael discuss auto_explain — what it is, how it can help, and how to check it's overhead. Here are links to a few things we mentioned:
auto_explain (docs)
ScaleGrid guide to auto_explain
Can auto_explain, with timing, have low overhead? (Blog post by Michael)
pgBadger
pg_stat_monitor
EXPLAIN ANALYZE may be lying to you (blog post by Álvaro from Ongres)
pg_test_timing
Our episode on benchmarking
Database Lab Engine
~~~What did you like or not like? What should we discuss next time? Let us know on YouTube, on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
4/28/2023 • 37 minutes, 18 seconds
Queues in Postgres
Nikolay and Michael discuss queues in Postgres — the pros and cons vs dedicated queuing tools, and some tips for scaling. A couple of apologies-in-advance:
Near the end, we incorrectly say "idempotent" when we meant "stateless", and also 50 TPS instead of 500 TPS
We also had a couple of audio issues, sorry!
Here are links to a few things we mentioned:
Recent discussion on Hacker News
PgQ
What is SKIP LOCKED (blog post by Craig Ringer)
autovacuum
Postgres queues (blog post by Brandur)
pg_repack
Our episode on partitioning
Nikolay’s Twitter poll
Subtransactions Considered Harmful (blog post by Nikolay)
~~~What did you like or not like? What should we discuss next time? Let us know on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
4/21/2023 • 39 minutes, 48 seconds
Read-only considerations
Nikolay and Michael discuss a listener request — special considerations for databases that are used in a read-only mode all day, and get an update at night with additional data.Here are links to a few things we mentioned:
Index-only scans
Vacuum
UK Covid-19 dashboard
pg_repack
Partitioning
Our episode on BRIN indexes
Always load sorted data (blog post by Haki Benita)
GIN indexes: the good and the bad (blog post by Lukas Fittl)
Our episode on materialised views
pg_buffercache
Towards Millions TPS (blog post by Alexander Korotkov)
Postgres WASM (by Snaplet and Supabase)
Yugabyte
AWS Aurora
Continuous Archiving and Point-in-Time Recovery (docs)
Our episode on checkpoint tuning
Our episode on partitioning
PgQ
Neon branching
Database Lab Engine
Cluster
~~~What did you like or not like? What should we discuss next time? Let us know on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
4/14/2023 • 39 minutes, 50 seconds
Partitioning
Nikolay and Michael discuss table partitioning — what it is, why and when it's helpful, and some considerations for your partition key. Here are links to a few things we mentioned:
Partitioning docs
pg_partman
Index maintenance episode
Timescale partitioning
pg_cron
Xtreme PostgreSQL (talk by Christophe Pettus)
Database Antipatterns (also by Christophe, slides 46-49)
Understanding an outage (blog post by Duffel)
~~~What did you like or not like? What should we discuss next time? Let us know on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)~~~Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
4/7/2023 • 34 minutes, 4 seconds
Peter Zaitsev
This week we're sharing an edited version of Nikolay's recent interview with Peter Zaitsev from Percona — they discuss MySQL vs Postgres, Percona’s success, open source licenses, FerretDB, and databases on Kubernetes… phew! And here are some links to a few things mentioned:
Percona
pgCloudHacker browser extension
PMM
Percona Distribution for PostgreSQL
FerretDB
Peter's Twitter profile
Peter's LinkedIn profile
------------------------What did you like or not like? What should we discuss next time? Let us know on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
3/31/2023 • 43 minutes, 15 seconds
psql vs GUIs
Nikolay and Michael discuss command line and graphical user interfaces for Postgres — what they are, some tips and tricks for learning, and what we each use and prefer. Here are links to a few things we mentioned:
psql (docs)
psql is awesome! (talk by Lætitia Avrot)
psql tips (site by Lætitia Avrot)
pgAdmin
Postico
DBeaver
DataGrip
PgManage (new Command Prompt fork of OmniDB)
PopSQL
postgres_dba
pspg
Materialized views episode
pgcli
------------------------What did you like or not like? What should we discuss next time? Let us know on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
3/24/2023 • 31 minutes, 12 seconds
Upgrades
Nikolay and Michael discuss major and minor version Postgres upgrades — what they are, how often they come out, and how regularly we should be upgrading. Here are links to a few things we mentioned:
Postgres versioning policy
why-upgrade (by depesz)
postgresqlco.nf (by Ongres)
postgresql.conf comparison (by Rustproof Labs)
pg_upgrade
Logical replication
CHECKPOINT
amcheck
Locale data changes (e.g. glibc upgrades)
ANALYZE
Upgrades are hard (summary of panel discussion by Andreas 'ads' Scherbaum)
spilo
Recent pgsql hackers discussion about using logical and pg_upgrade together
------------------------What did you like or not like? What should we discuss next time? Let us know on social media, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
3/17/2023 • 40 minutes, 18 seconds
Wait events
Nikolay and Michael discuss wait events — what they are, why we have them, and how to use them to help diagnose performance issues. Here are links to a few things we mentioned:
Wait events table (docs)
9.6 release notes
PostgreSQL Scalability (blog post by Alexander Korotkov)
Wait event analysis in pganalyze
auto_explain
Database Lab Engine
track_io_timing
pg_test_timing
pgBadger
Coroot
Okmeter
pgwatch2 Postgres.ai Edition
pg_wait_sampling
pgsentinel
Datadog
AWS RDS docs for PostgreSQL wait events
pgMustard newsletter
PASH Viewer
pgCenter
Intro to query optimisation episode
Monitoring checklist episode
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
3/10/2023 • 31 minutes, 23 seconds
TOAST
Nikolay and Michael discuss TOAST (The Oversized-Attribute Storage Technique) — what it is, how it works, and some general things to be aware of. Here are links to a few things we mentioned:
TOAST docs
TOAST wiki
Hussein Nasser on rows per page (Twitter)
Toasting in action (dbi services blog)
Interview with Peter Zaitsev (Postgres TV)
Building columnar compression in a row-oriented database (Timescale blog post)
The Surprising Impact of Medium-Size Texts on PostgreSQL Performance (blog post by Haki Benita)
PostgreSQL at Scale: Saving Space Basically for Free (blog post by Braintree on column Tetris)
postgres_dba alignment padding query
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
3/3/2023 • 28 minutes, 11 seconds
JSON
Nikolay and Michael discuss JSON — our options for storing it in Postgres, whether or when we should, as well as a brief intro and some tips for JSON functions available. Here are links to a few things we mentioned:
hstore
XML type
XML functions
JSON types
JSON functions
JSONB indexing
NULLS episode
Why Postgres is popular episode
PostgreSQL 12 release notes
What’s New in SQL:2016 (blog post by Markus Winand)
SQL/JSON is postponed (blog post by depesz)
JSON[b] Roadmap (talk by Oleg Bartunov)
Slides, with benchmarks
RUM access method
JSON in PostgreSQL: how to use it right (blog post by Laurenz Albe from Cybertec)
pg_jsonschema
TOAST_TUPLE_TARGET and TOAST_TUPLE_THRESHOLD
The Surprising Impact of Medium-Size Texts on PostgreSQL Performance (blog post by Haki Benita)
Aggregate functions
How to store and index json data (blog post by ScaleGrid)
When to avoid JSONB (blog post by Heap)
FerretDB
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
2/24/2023 • 31 minutes, 59 seconds
Real-time analytics
Nikolay and Michael discuss real-time analytics — what it means, what the options are, and some tips if you're trying to implement it within Postgres. Here are links to a few things we mentioned:
Loose index scan / skip scan with recursive CTE (wiki)
Zheap (wiki)
cstore_fdw (now part of Citus)
Timescale compression docs
Hydra founders interview (on Postgres TV)
Materialised views episode
pg_ivm
Timescale continuous aggregates docs
Clickhouse
Snowflake
Replication episode
Timescale bottomless storage on S3 (blog post)
pg_partman
Querying Postgres from DuckDB (blog post)
Heap blog (filter by “Engineering”)
Incremental View Maintenance (wiki)
PostgreSQL HyperLogLog
Faster counting (by Joe Nelson on the Citus blog)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
2/17/2023 • 34 minutes, 2 seconds
Benchmarking
Nikolay and Michael discuss benchmarking — reasons to do it, and some approaches, tools, and resources that can help. Here are links to a few things we mentioned:
Towards Millions TPS (blog post by Alexander Korotkov)
Episode on testing
Episode on buffers
pgbench
sysbench
Improving Postgres Connection Scalability (blog post by Andres Freund)
pgreplay
pgreplay-go
JMeter
pg_qualstats
pg_query
Database experimenting/benchmarking (talk by Nikolay, 2018)
Database testing (talk by Nikolay at PGCon, 2022)
Systems Performance (Brendan Gregg’s book, chapter 12)
fio
Netdata
Subtransactions Considered Harmful (blog post by Nikolay including Netdata exports)
WAL compression benchmarks (by Vitaly from Postgres.ai)
Dumping/restoring a 1 TiB database benchmarks (by Vitaly from Postgres.ai)
PostgreSQL on EXT3/4, XFS, BTRFS and ZFS (talk slides from Tomas Vondra)
Insert benchmark on ARM and x86 cloud servers (blog post by Mark Callaghan)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
2/10/2023 • 36 minutes, 46 seconds
Default configuration
Nikolay and Michael discuss the default config — some tools and principles you can use to customise it, as well as several parameters you probably always want to change.Here are links to a few things we mentioned:
shared_buffers
Andres Freund tweets about shared_buffers
PGTune Leopard
Cybertec Configurator
pg_stat_statements
JIT configuration
postgresqlco.nf
annotated.conf
OtterTune
work_mem
random_page_cost
max_connections
What to log
max_wal_size
WAL and checkpoint tuning episode
effective_cache_size
Intro to Performance Tuning and Optimization (EDB guide)
max_parallel_workers_per_gather
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
2/3/2023 • 32 minutes, 21 seconds
Infra cost optimization
Here are links to a few things we mentioned:
The Cost of Cloud, a Trillion Dollar Paradox (blog post from Andreessen Horowitz)
OVH
Hetzner
postgresql_cluster
Why we're leaving the cloud (blog post by DHH from Basecamp)
Managed services vs. DIY episode
ec2instances.info
Vantage
Postgres TV episode with Everett Berry from Vantage
Migrating to Aurora: easy except the bill (blog post by Kimberly Nicholls from Gridium)
Database Lab Engine
Postgres.ai consulting
Netdata
sysbench
fio
Query macro analysis episode
Top queries by buffers (Gist from Michael)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
1/27/2023 • 28 minutes
Auditing
Here are links to a few things we mentioned:
Crunchy Data PostgreSQL Security Technical Implementation Guide (STIG)
pgAudit (site)
pgAudit (repo)
noset (extension)
Splunk
Kibana
Timescale
CREATE TRIGGER docs
Transition table triggers (blog post by David Fetter)
Table Audit (blog post by Lorenzo Alberton)
Row change auditing options (blog post by CYBERTEC)
Hydra founders interview (on Postgres TV)
max_slot_wal_keep_size
eBPF
Building a perf-like tool for PostgreSQL (talk by Ronan Dunklau)
Party tricks for PostgreSQL: perf, ftrace and bpftrace (talk by Dmitry Dolgov)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
1/20/2023 • 35 minutes, 32 seconds
Copying a database
Here are links to a few things we mentioned:
pg_dump
pg_restore
pgcopydb (tool by Dimitri Fontaine)
pg_dump and external snapshots (blog post by Michael Paquier)
Systems Performance (book by Brendan Gregg)
Performance troubleshooting methodologies (two part talk by Brendan Gregg)
pg_basebackup
wal-g
pgBackRest
Database Lab Engine
Database branching episode
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
1/13/2023 • 39 minutes, 25 seconds
Transaction ID wraparound
Here are links to a few things we mentioned:
The Internals of PostgreSQL chapter 5 (book by Hironobu SUZUKI)
PostgreSQL 14 internals chapter 7 (book by Egor Rogov)
Transaction ID Wraparound (blog post from Sentry)
What We Learned from the Recent Mandrill Outage (blog post from Mailchimp)
How to simulate transaction ID wraparound (blog post by Prashant Dixit)
Add 64-bit XIDs into PostgreSQL 16 (commitfest entry)
Partitioning (docs)
Consider using VACUUM’s INDEX_CLEANUP option (tweet by Peter Geoghan)
Add wraparound failsafe to VACUUM (commit)
Do you vacuum everyday? (talk by Hannu Krosing)
Multixacts wraparound monitoring (mailing list thread)
Subtransactions Considered Harmful (blog post by Nikolay)
Buffer management in PostgreSQL (talk by Alexander Korotkov)
OrioleDB
pageinspect
pg_hexedit
pg_visibility
Visibility Map (docs)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
1/6/2023 • 35 minutes, 14 seconds
Postgres year in review 2022
Here are links to a few things we mentioned: 1. Startups building momentum
Aiven raised $210m
Timescale raised $110m
Hasura raised $100m
Supabase raised $80m
Neon raised $30m
Hydra
OrioleDB
2. Educational resources
Postgres FM started 👋
Postgres TV became more active (including topic playlists)
Tobias Petry tips on Twitter and SQL for Devs
Hussein Nasser YouTube channel (backend engineering)
Postgres Weekly (newsletter)
3. Sharding progress
Citus goes fully open source
SPQR
pgcat
Sharding Postgres at Notion (blog post)
PlanetScale (MySQL)
4. Database branching is coming
Database Lab Engine
Neon branching
OrioleDB branching
Crunchy Bridge
Database branching episode
5. Postgres is everywhere
All cloud providers
AlloyDB announced
Kubernetes operators (comparison blog post)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/30/2022 • 33 minutes, 26 seconds
Row estimates
Here are links to a few things we mentioned:
ANALYZE (docs)
Autovacuum config (docs)
Statistics used by the planner (docs)
CREATE STATISTICS (docs)
Row count estimates (pgMustard blog post)
pg_hint_plan
Optimizer methodology (talk by Robert Haas)
Tomáš Vondra on statistics and hints (an excellent interview we forgot to mention, sorry!)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/23/2022 • 31 minutes, 51 seconds
Replication
Here are links to a few things we mentioned:
Replication (docs)
9.0 release notes (including built-in replication)
Slony
Londiste
pg_is_in_recovery (pgPedia page)
Patroni
Multiple Databases with Active Record
hot_standby_feedback (docs)
max_standby_archive_delay or max_standby_streaming_delay (for WAL-shipping and WAL-streaming respectively)
synchronous_commit
Synchronous replicas
Database Lab Engine
Neon Branching
Past, Present, and Future of Logical Replication (Postgres TV with Amit Kapila)
Failover of logical replication slots in Patroni (Postgres TV with Alexander Kukushkin)
PostgreSQL Subtransactions Considered Harmful (blog post by Nikolay)
Why we spent the last month eliminating PostgreSQL subtransactions (blog post by GitLab)
Fivetran
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/16/2022 • 37 minutes, 56 seconds
Timestamps
Here are links to a few things we mentioned:
Date/Time Types (docs)
Don’t use timestamp without time zone (wiki)
Date/Time functions and operators (docs)
Postgres AT TIME ZONE explained (blog post by Bruce Momjian)
Our episode on BRIN indexes
RUM indexes
allballs (mailing list thread)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/9/2022 • 26 minutes, 18 seconds
PostgREST
Here are links to a few things we mentioned:
PostgREST documentation
Supabase
No offset (blog post by Markus Winand)
JSON functions and operators (PostgreSQL docs)
Stored procedures (a previous Postgres FM episode)
PostGraphile
Hasura
Parse, Inc.
Firebase
PostgresML
PgQ
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
12/2/2022 • 29 minutes, 5 seconds
Materialized views
Apologies, Michael's audio is not great in this, we'll hopefully be back to normal next week!Here are links to a few things we mentioned:
Materialized views (docs)
Refresh materialized view (docs)
Timescale blog post
PlanetScale Boost (content warning: MySQL)
Incremental Materialized Views with pg_ivm (video by Lukas Fittl)
Articles on how to do your own incremental updates(?)
Materialize (company)
Materialize talk
Incremental View Maintenance (Postgres wiki)
Implementing Incremental View Maintenance (mailing list thread)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/25/2022 • 41 minutes, 3 seconds
HOT updates
Here are links to a few things we mentioned:
Heap-only tuple updates (docs)
README file (source code)
Heap Only Tuple chapter (Internals of PostgreSQL by Hironobu SUZUKI)
How partial, covering, and multicolumn indexes may slow down UPDATEs (blog post by Nikolay)
Why Uber switched from Postgres to MySQL (blog post)
Fighting write amplification with HOT updates (Adyen blog post)
HOT Updates vs Bottom-Up Index Deletion (video by Lukas Fittl from pganalyze)
Reduced Bloat with Bottom-Up Deletion (blog post by Hamid Akthar from Percona)
What is fillfactor and how does it affect performance? (blog post by Kaarel Moppel from Cybertec)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/18/2022 • 30 minutes, 13 seconds
Database branching
Here are links to a few things we mentioned:
Database Lab Engine
Overview of Aurora cloning
PlanetScale branching
Common DB schema change mistakes (blog post by Nikolay)
Supabase vision
Neon branching
Shift-left testing
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/11/2022 • 31 minutes, 15 seconds
Version control for databases
Here are links to a few things we mentioned:
A brief history of Version Control Systems (blog post by Mehran Hajirajabi)
Redgate Source Control for Oracle (and SQL Server)
Flyway
Sqitch
Liquibase
pgAdmin Schema Diff
Migra
PostgresCompare
Schema based versioning and deployment (blog post by Valentine Gogichashvili)
Change management tools and techniques (PostgreSQL Wiki)
GitLab migration_helpers.rb
Database schema changes without downtime (blog post by James Coleman from Braintree/PayPal)
Zero-downtime Postgres schema migrations need lock_timeout and retries (blog post by Nikolay)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
11/4/2022 • 31 minutes, 21 seconds
Contributing to Postgres
Here are links to a few things we mentioned:
PostgreSQL 14 coin (upside down!)
Intro to Planner Hacking (talk by Melanie Plageman)
Demystifying contributing to PostgreSQL (talk by Lætitia Avrot)
How to become a PostgreSQL contributor (blog post by Aleksander Alekseev)
Compile and install from source code (PostgreSQL Wiki)
PostgreSQL mailing lists
GitHub PostgreSQL mirror
GitLab PostgreSQL mirror
Commitfests
So, you want to be a developer? (PostgreSQL Wiki)
Resolving the search engine issue (mailing list thread)
Planet PostgreSQL
pg_stat_monitor (extension by Percona)
ZomboDB
pgx (framework for developing extensions)
Awesome Postgres
Depesz blog
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/28/2022 • 33 minutes, 7 seconds
Stored procedures
Here are links to a few things we mentioned:
Extending SQL
PostgREST
PL/pgSQL
EdgeDB
pgTAP
Sqitch
Flyway
Liquibase
client_min_messages
log_min_messages
RAISE DEBUG
Simplify: move code into database functions (blog post by Derek Sivers)
PL/sh
Supabase
auto_explain.log_nested_statements
Hasura
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov / @michristofides / @PostgresFM, or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/21/2022 • 35 minutes, 47 seconds
PostgreSQL 15
Here are links to a few things we mentioned:
PostgreSQL 15 release notes
Speeding up sort performance in Postgres 15 (blog post by David Rowley)
Past, Present, and Future of Logical Replication (talk by Amit Kapila)
Postgres 15 improves UNIQUE and NULL (blog post by Ryan Lambert)
Do you vacuum everyday? (talk by Hannu Krosing)
Why upgrade PostgreSQL? (by depesz)
What did you like or not like? What should we discuss next time? Let us know by tweeting us on @PostgresFM or by commenting on our topic ideas Google doc.If you would like to share this episode, here's a good link (and thank you!)------------------------Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/14/2022 • 29 minutes, 39 seconds
102 Query optimization
Here are links to a few things we mentioned:
pg_plan_advsr
How partial, covering, and multicolumn indexes may slow down UPDATEs (blog post by Nikolay)
Why Uber Switched from Postgres to MySQL (blog post)
pganalyze index advisor
Nancy bot (project is not active)
pgreplay
pgreplay go
Real Application Testing on YugabyteDB with pgreplay (blog post by Franck Pachot)
pg_query
Database Lab thin clones
Migrating to Aurora: easy except the bill (blog post by Kimberley Nicholls)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @PostgresFM or by commenting on our topic ideas Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
10/7/2022 • 31 minutes, 28 seconds
Why is Postgres popular?
This episode was badly affected by internet issues. Hopefully the edit came out ok, but the quality should be back to a better level from next week.Here are links to a few things we mentioned:
Monthly blog event, PGSQL Phriday (blog post from Ryan Booz)
Who or what made Postgres cool? (tweet from Kenneth Cassel)
PostGIS
Acquisition of Sun by Oracle
DB-Engines trend
Hacker News hiring trends
Supabase on GitHub (nearly 40k stars)
How I Built This (podcast)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @PostgresFM or by commenting on our topic ideas Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/30/2022 • 31 minutes, 1 second
Index maintenance
Important correction from this episode: amcheck promises no false positives, not no false negatives, sorry!Here are links to a few things we mentioned:
pgstattuple
pg_repack
postgres-checkup
Workload Analysis for GitLab.com
Bloat Analysis (also from GitLab)
Bloat, pg_repack, and deferred constraints (blog post by Miro)
amcheck
Peter Geoghegan interview (on Postgres TV)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofides or by commenting on our topic ideas Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/23/2022 • 32 minutes, 41 seconds
Query macro analysis intro
Here are links to a few things we mentioned:
pg_stat_statements
pgFouine
pgBadger
pg_query
pg_stat_activity
auto_explain
Can auto_explain (with timing) have low overhead? (blog post by Michael)
track_io_timing
pgbench
PgHero
pgCenter
pgwatch2 (Postgres AI edition)
pg_stat_kcache
PASH Viewer
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofides or by commenting on our topic ideas Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/16/2022 • 33 minutes, 29 seconds
WAL and checkpoint tuning
Here are links to a few things we mentioned:
LSN (log sequence number)
On the impact of full-page writes (blog post by Tomas Vondra)
Deep dive on Aurora Postgres (talk by Grant McAlister)
Netdata monitoring
PostgresqlCO.NF
pgPedia
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofides or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/9/2022 • 37 minutes, 46 seconds
Intro to query optimization
Here are links to a few things we mentioned:
Using EXPLAIN (PostgreSQL documentation)
explain.depesz.com
explain.dalibo.com
pgMustard
EverSQL
pganalyze
pg_stat_monitor (Extension by Percona)
Recent thread on hackers mailing list about plan_id in pg_stat_activity
auto_explain
EXPLAIN observer effect (Ongres blog post by Álvaro Hernández)
auto_explain overhead (blog post by Michael)
pg_test_timing
Database Lab Engine (for thin clones)
Our previous episode on BUFFERS
EXPLAIN Explained (talk by Josh Berkus)
A beginner's guide to EXPLAIN (talk by Michael)
A deeper dive into EXPLAIN (talk by Michael)
EXPLAIN glossary (pgMustard docs)
Topic suggestions document
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofides or by commenting on our Google doc.If you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
9/2/2022 • 33 minutes, 14 seconds
How to become a DBA
And few things we mentioned:
Topic request on Reddit — thanks HerbyHoover!
Haki Benita's blog
PostgreSQL documentation (table of contents)
Planet PostgreSQL (blog aggregator)
MVCC Unmasked (by Bruce Momjian)
The Internals of PostgreSQL (by Hironobu SUZUKI)
PostgreSQL 14 Internals — parts I and II (by Egor Rogov)
Cybertec blog
modern-sql.com (by Markus Winand)
use-the-index-luke.com (by Markus Winand)
The Art of PostgreSQL (by Dimitri Fontaine)
explain.depesz.com
explain.dalibo.com
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/26/2022 • 32 minutes, 31 seconds
Monitoring checklist
Monitoring checklist (dashboard 1):
TPS and (optional but also desired) QPS
Latency (query duration) — at least average. Better: histogram, percentiles
Connections (sessions) — stacked graph of session counts by state (first of all: active and idle-in-transaction; also interesting: idle, others) and how far the sum is from max_connection (+pool size for PgBouncer).
Longest transactions (max transaction age or top-n transactions by age), excluding autovacuum activity
Commits vs rollbacks — how many transactions are rolled back
Transactions left till transaction ID wraparound
Replication lags / bytes in replication slot / unused replication slots
Count of WALs waiting to be archived (archiving lag)
WAL generation rates
Locks and deadlocks
Basic query analysis graph (top-n by total_time or by mean_time?)
Basic wait event analysis (a.k.a. “active session analysis” or “performance insights”)
And links to a few things we mentioned:
Postgres monitoring review checklist (community document)
pgstats.dev
Improving Postgres Connection Scalability: Snapshots (blog post by Andres Freund)
Transaction ID Wraparound in Postgres (blog post by David Cramer)
Subtransactions Considered Harmful (blog post by Nikolay)
datadoghq.com
pgwatch2 (Postgres.ai Edition)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/19/2022 • 27 minutes, 1 second
Vacuum
Here are links to a few things we mentioned:
Do you vacuum everyday? (talk by Hannu Krosing)
Autovacuum tuning (EDB guide)
When autovacuum does not vacuum (2ndQuadrant blog post by Tomas Vondra)
Autovacuum tuning basics (old 2ndQuadrant blog post)
Discussion with Anastasia Lubennikova (on RuPostgres, in Russian)
B-tree indexes (talk by Anastasia Lubennikova, in English)
Discussion with Peter Geoghegan (on Postgres TV)
pg_repack
pg_squeeze
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/12/2022 • 32 minutes, 21 seconds
NULLs: the good, the bad, the ugly, and the unknown
Here are links to a few things we mentioned:
Three-valued_logic (Wikipedia)
Postgres 15 improves UNIQUE and NULL (blog post by Ryan Lambert)
Practical SQL for Data Analysis — Interpolation (blog post by Haki Benita)
What is the deal with NULLs? (blog post by Jeff Davis)
NULL in SQL: Indicating the Absence of Data (Markus Winand on Modern SQL)
The Art of PostgreSQL (book by Dimitri Fontaine)
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
8/5/2022 • 27 minutes, 10 seconds
BUFFERS by default
Here are links to a few things we mentioned:
EXPLAIN parameters (PostgreSQL documentation)
EXPLAIN (ANALYZE) needs BUFFERS (blog post by Nikolay)
Using BUFFERS for query optimization (blog post by Michael)
H3 indexes on PostGIS data (blog post by Ryan Lambert)
Turning BUFFERS on by default (latest patch)
pgMustard
explain.depesz.com
explain.dalibo.com
Database Lab Engine
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
7/29/2022 • 33 minutes, 58 seconds
BRIN indexes
Here are links to the two main resources we mentioned:
Paul Ramsey's recent blog post on BRIN indexes
Tomas Vondra's slides on BRIN index improvements
A few other things we mentioned:
B-tree Wikipedia page
pg_repack
pg_squeeze
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
7/21/2022 • 36 minutes, 7 seconds
Managed services vs. DIY
A well as discussing pros and cons, we mentioned a LOT of different providers and tools, and a few good articles/videos too. 😅Here are links to most of them, roughly in the order they came up:
How Auto Trader migrated its on-prem databases to Cloud SQL
PostgreSQL Community Panel: Upgradability
Postgres TV Open Talks
PostgreSQL Conference Europe
Hannu Krosing — excellent vacuum talk
pg_docs_bot — browser extension for getting to the current docs
Amazon RDS for PostgreSQL
Google Cloud SQL for PostgreSQL
Heroku Postgres
Crunchy Bridge
Spilo: HA PostgreSQL Clusters with Docker
Aiven for PostgreSQL
AlloyDB for PostgreSQL
Neon
Yugabyte
ScaleGrid PostgreSQL Hosting
StackGres
Timescale
OrioleDB
Citus
Supabase
PlanetScale
pg_stat_kcache
pg_wait_sampling
EDB BigAnimal
Azure Database for PostgreSQL
------------------------What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork
7/14/2022 • 32 minutes, 52 seconds
Slow queries and slow transactions
What did you like or not like? What should we discuss next time? Let us know by tweeting us on @samokhvalov and @michristofidesIf you would like to share this episode, here's a good link (and thank you!)Postgres FM is brought to you by:
Nikolay Samokhvalov, founder of Postgres.ai
Michael Christofides, founder of pgMustard
With special thanks to:
Jessie Draws for the amazing artwork