Shard Balancing: Moving Shops Confidently with Zero-Downtime at Terabyte-scale

Shopify rebalances MySQL shards by moving individual shops online with its Ghostferry tool.

Published
2021-09-24
Scale
terabyte scale
Techniques
shard rebalancing online migration zero downtime
Stack
MySQL Ghostferry

Try this stack yourself

  • Railway · Deploy something like this on Railway: spin up MySQL 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 Shopify'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 Shopify'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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