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I would partially agree with you and partially disagree, but overall, it's probably not the best behaviour here. Rather than informing the app that there are no more packets, I would say instead that it incorrectly informs the app that the descriptor ring is not potentially overloaded. The reason for the difference is that, even in the case of a driver correctly returning any number of packets, by the time the function returns there could always be more in the ring. Where the real risk, IMHO, is that you could miss out on a ring filling up without being aware of it, because a full burst is a warning sign of overload. /Bruce > [1]: https://elixir.bootlin.com/dpdk/v25.07-rc2/source/drivers/net/intel/i40e/i40e_rxtx.c#L640 > > PS: I stumbled across this while reviewing how the very old 32 packet limit bugs (where it truncated large rx/tx requests to 32 packets) had been fixed. >