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Subject: Re: rte_eth_tx_burst() always returns 0 in tight loop
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Dear Antonio,

According to my experience, the rte_eth_tx_burst() function reports the 
packets as "sent" (by a non-zero return value), when they are still in 
the transmit buffer.

(If you are interested in the details, you can see them in Section 3.6.5 
of this paper: http://www.hit.bme.hu/~lencse/publications/e104-b_2_128.pdf )

Therefore, I think that the return value of 0 may mean that 
rte_eth_tx_burst() can't even commit itself for the future delivery of 
the packets. I could only guess why. E.g. all its resources have been 
exhausted.

Best regards,

Gábor


7/3/2022 5:57 PM keltezéssel, Antonio Di Bacco írta:
> I'm trying to send packets continuously in a  tight loop with a burst
> size of 8 and packets are 9600 bytes long.
> If I don't insert a delay after the rte_eth_tx_burst it always returns 0.
>
> What's the explanation of this behaviour ?
>
> Best regards,
> Antonio.