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Date: Mon, 29 Jun 2015 10:18:32 +0100
From: Bruce Richardson <bruce.richardson@intel.com>
To: "Assaad, Sami (Sami)" <sami.assaad@alcatel-lucent.com>
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Subject: Re: [dpdk-dev] 10G Interface used as PCI Pass-Through reports
 64bytes / packet
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On Fri, Jun 26, 2015 at 04:56:18PM +0000, Assaad, Sami (Sami) wrote:
> Hello,
> 
> Is it normal that a 10G NIC interface, supporting the 82599 Ethernet Controller, configured as PCI Pass-through for a virtual machine using DPDK,  reports 64 bytes per packet; no matter what the packet size?
> 
That would not be expected behaviour, no.
AFAIK, the 82599 NIC counters should behave in the same way whether or not it is passed through
to a VM or used on a host. 

> If so; I'm assuming this is to improve the performance of passing the network traffic to the VM.  Is there a way to configure the NIC to properly present the proper byte count/packet?
> 
I'm not sure what you mean here. I can't see how the reporting of byte-counts
would affect performance. Can you clarify what exactly you are seeing, and why
you think there is a performance benefit because of it?

/Bruce

> Thanks in advance.
> 
> Best Regards,
> Sami.