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A UDR may be queued up while another thread is busy processing a reference to it. Workflows routing the same UDR on several routes and involving further processing of its data, must consequently be reconfigured to avoid this. A simple workaround is to route the UDR to an Analysis agent for cloning before routing it to the other agents (one unique clone per route). See discussion under 9.6.4 Analysis Agent Assignment and Cloning about the potential problems with multiple agents processing the same UDR in parallel.
Analyzing Thread Buffer Statistics
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