THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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The replica fetcher threads are handling multiple partitions. In case a partition fails, the the replica fetcher thread associated with that partition terminates. The partitions that have caught up and are running well are also left untracked with termination of the thread. A better approach would be, whenever a partition crashes, the concerned thread should stop tracking the crashed partition and continue handling rest of the partitions.
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