Partitioning GitHub's relational databases to handle scale

GitHub defined schema domains and linted cross-domain queries so it could move table groups onto separate MySQL clusters.

Published
2021-09-27
Scale
Not stated in source
Techniques
vertical partitioning schema domains online migration
Stack
MySQL Ruby on Rails Vitess

Try this stack yourself

  • Railway · Deploy something like this on Railway: spin up MySQL and Ruby on Rails 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 GitHub'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 GitHub'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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