Breaking up with Mnesia

on YouTube ↗37m

" summary

Klarna migrates a 15-year Mnesia deployment to Postgres by adding a compatibility API and a distribution layer so both databases appear as one; built a proprietary KDB replication layer, a LevelDB Mnesia backend and index-as-tables hacks. Postgres mimics Mnesia serializability with advisory locks for missing rows and a custom transaction tester; property tests validate type encoding and ordering. Heavy batch jobs drop from ~48 hours to 5–6 hours after introducing multiops and optimizations; 5 TB restores into test complete in ~20 minutes.

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" chapters (9)

1. 0:0002:18 - Introduction
2. 2:1906:51 - Problems with Mnesia
3. 6:5211:04 - The road to Postgres : Migration Plan
4. 11:0514:30 - The road to Postgres : Isolation Levels
5. 14:3116:19 - The road to Postgres : Types
6. 16:2018:04 - The road to Postgres : QLCs
7. 18:0522:23 - The road to Postgres : Property based tests
8. 22:2426:37 - Things we will mess from Mnesia
9. 26:3836:58 - QnA

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