The Great Re-shard: adding Postgres capacity (again) with zero downtime

Notion tripled its Postgres fleet by re-sharding with logical replication and careful PgBouncer cutovers, with no downtime.

Published
2023-07-17
Scale
Not stated in source
Techniques
resharding logical replication zero downtime
Stack
PostgreSQL PgBouncer

Try this stack yourself

  • Railway · Deploy something like this on Railway: spin up PostgreSQL plus your app in a few clicks. New accounts get $20 in credit (applied when you pick a paid plan).
    Railway isn't part of Notion's setup in this story. It's just an easy place to try the same building blocks.
  • Better Stack · Monitor uptime and logs with Better Stack, and get alerted fast if a migration or traffic spike goes sideways on your own system.
    Better Stack isn't part of Notion's setup in this story. It's a tool for watching your own systems while you try ideas like these.

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See also

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