Github user joewitt commented on the issue: https://github.com/apache/nifi/pull/2657 @viazovskyi I just noticed this processor is trigger serially which means it isn't designed for concurrent use and in nifi will only ever have one thread. So we can relax on the check/modify piece. I think you want the flag reset lower in the block (end of try inside try/catch closer to where it was).
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