Add dummy writes for get-all to check the confict #126
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brfrn169
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May 29, 2024
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| ;; Need Storage API to read the transaction metadata | ||
| (let [tx-result (.get tx (prepare-get i)) | ||
| result (.get storage (prepare-get i))] | ||
| ;; Put the same balance to check conflicts with in-flight transactions | ||
| (->> (calc-new-balance tx-result 0) | ||
| (prepare-put i) | ||
| (.put tx)) | ||
| result) |
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I think I missed something, but I thought the transactional Get can also detect conflicts with in-flight transactions (by throwing UncommittedRecordException). Why do we need this additional dummy write?
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Read skew could happen because this is a read-only transaction when the isolation level is snapshot isolation.
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Understood. So it's like a manual EXTRA_WRITE. Thanks.
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Description
The
get-alltransaction to get all records for the consistency check gets some inconsistency results.In a Jepsen test, the
final-generatorgenerates the operation after the main generator finishes, but it doesn't check the completion.So,
get-allgenerated byfinal-generatorcould start before the all transactions were completed.They were just a read-only transactions and didn't check the conflict with in-flight transactions.
This PR adds the dummy writes to these
get-alltransactions to check the conflict.Related issues and/or PRs
Changes made
get-alltransactionsChecklist
Additional notes (optional)