In summary, this TLA+ specification models a system with two parallel processes simulating user actions on objects stored in databases. Users randomly perform either Upsert or Delete operations twice each on predefined objects while maintaining identical actions across systems with and without migration support (WOMigration vs. WMigration). A background migration process continuously copies data from olddb to newdb, ensuring atomicity during object creation if it doesn’t exist in the destination database already. TLA+ proves valuable by detecting design flaws early on, highlighting necessary steps for atomicity and exposing potential issues that may arise due to concurrent execution or missing edge cases.
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