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Date: Wed, 10 Dec 2014 11:22:34 +0000
From: Bruce Richardson <bruce.richardson@intel.com>
To: Sachin Sharma <sharonsachin@gmail.com>
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Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] transmit functions of dpdk
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On Wed, Dec 10, 2014 at 12:03:41PM +0100, Sachin Sharma wrote:
> Dear all,
> 
>  In my algorithm, I am interested to perform  two activities - (1)
> transmitting packets to a tx_queue and (2) transmitting packets from
> tx_queue to a wire - separately. I have gone through the code by putting
> logs in the dpdk code and found that there is a function rte_eth_tx_burst
> which transmits packets to a specific queue. However, when I debugged more
> then I found that this function just calls eth_igb_xmit_pkts
> from librte_pmd_e1000, and this function just directly write the packets to
> the wire by writing all packets into registers. Could you please suggest
> how to implement these two functions if these are not implemented already
> in dpdk?
> 
> 
> 
> Thanks & Regards,
> Sachin.

Hi Sachin,

anything written to the NIC TX queue is automatically put onto the wire unless
the NIC port is down or the wire is unplugged etc. What is your use-case that you
need to do this? I would suggest doing internal buffering in your application,
as many DPDK example applications do, and then call tx_burst to put your packets
on the wire when you want this capability.

Regards,
/Bruce