fix: prevent infinite loop in balanceHighestNode on selector error#895
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mattisonchao merged 1 commit intomainfrom Feb 24, 2026
Merged
fix: prevent infinite loop in balanceHighestNode on selector error#895mattisonchao merged 1 commit intomainfrom
mattisonchao merged 1 commit intomainfrom
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When swapShard returned an error, the continue statement skipped shardIter.Prev(), leaving the iterator on the same shard. This caused the loop to retry the same shard forever, hanging the balancer goroutine. Always advance the shard iterator regardless of the swap result. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
merlimat
approved these changes
Feb 23, 2026
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Motivation
In
balanceHighestNode, whenswapShardreturned a non-nil error,continueskippedshardIter.Prev(). The iterator stayed on the same shard, retrying it forever. This hangs the balancer goroutine. Happens when anti-affinity isStrictand no valid placement exists.Modification
continueafter the error logTestBalanceHighestNodeDoesNotHangOnSelectorErrorusing a selector that always returnsErrUnsatisfiedAntiAffinity, verifyingrebalanceEnsemble()completes without hanging