The Importance of Shared Buffers in Postgres

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

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

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Postgres FM is 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