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Add live migration from postgres #2759
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Add live migration from postgres
alejandrodnm 75cff10
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Add prepare source section
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Populate live migration index page
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--- | ||
title: Live migration | ||
excerpt: Migrate an entire database with low downtime | ||
products: [cloud] | ||
keywords: [migration, low-downtime, backup] | ||
tags: [recovery, logical backup, replication] | ||
--- | ||
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# Live migration | ||
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Live migration is a migration strategy to move a large amount of data | ||
(100 GB-10 TB+) with low downtime (on the order of minutes of | ||
downtime). It is significantly more complicated to execute than a migration | ||
with downtime using [pg_dump/restore][pg-dump-and-restore], but supports more | ||
use-cases and has less requirements than the [dual-write and backfill] method. | ||
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<SourceTargetNote /> | ||
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Live migration leverages Postgres' built-in replication functionality to | ||
provide a seamless migration with very little application downtime. | ||
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Roughly, it consists of four steps: | ||
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1. Prepare and create replication slot in source database. | ||
2. Copy schema from source to target, optionally enabling hypertables. | ||
3. Copy data from source to target while capturing changes. | ||
4. Apply captured changes from source to target. | ||
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Currently live migration only supports migrating from PostgreSQL, but we are | ||
actively working on supporting TimescaleDB. | ||
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Live migration works well when: | ||
- Large, busy tables have primary keys, or don't have many `UPDATE` or | ||
`DELETE` statements. | ||
- The insert workload does not exceed 20'000 rows per second, and | ||
inserts are batched. If your application exceeds this, you should use | ||
the [dual-write and backfill] migration method. | ||
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For more information, consult the step-by-step migration guide: | ||
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- [Live migration from PostgreSQL][from-postgres] | ||
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[from-postgres]: /migrate/:currentVersion:/live-migration/live-migration-from-postgres/ | ||
[pg-dump-and-restore]: /migrate/:currentVersion:/pg-dump-and-restore/ | ||
[dual-write and backfill]: /migrate/:currentVersion:/dual-write-and-backfill/ |
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This isn't true but this PR should address this.