Fix(core): Fix deadlock in runMutation and error handling #9085
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dgraph-bot
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area/core
harshil-goel
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mangalaman93
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May 19, 2024
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We call txn.Update() once the transaction has finished. This moves all the uncommited posting lists to a delta map in the txn. This can cause a deadlock with runMutation. Mostly we have seen it when a transaction has a timeout. RunMutation keeps on going, while txn.Update() gets triggered. This PR fixes it by not calling txn.Update() if the transaction has failed. We would futher look into cancelling runMutation at that time too.
Fixes: https://linear.app/hypermode/issue/DGR-477/dgraph-v24-alpha-2-hangs