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Hello,
   recently, i use rally to test boot-and-delete. I thought that one nova-scheduler will handle message sent to it one by one, but the log print show differences. So Can some one how nova-scheduler handle messages? I read the code in nova.service,  and found that one service will create fanout consumer, and that all fanout message consumed in one thread. So I wonder that, How the nova-scheduler handle message, if there are many messages casted to call scheduler's run_instance?
Thanks a lot.
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