[CentOS] Intel 82579V ethernet nic using only one IRQ? (Dual TX RX queues)

Sun Jun 9 17:09:56 UTC 2013
Alex Flex <aflexzor at gmail.com>

Hello John,

Thanks for the informative reply, do you know what Intel would mean by 
advertising the NIC with "Performance — Two Queues (Tx & Rx) " then?

If i understand you correctly, are you confirming to me that only a Dual 
port NIC will deliver different IRQs?


On 06/08/2013 11:44 PM, John R Pierce wrote:
> wait, the 82579 is just a PHY layer for the Intel 6 Series Express CPU 
> chipset's built in MAC (p67, z68, hm67, etc chipsets for the Sandy 
> Bridge family of desktop/mobile CPUs). That combination is also a 
> 'entry level' desktop/workstation or 'mobile embedded' grade ethernet 
> interface, not really a server grade interface at all. regardless, its 
> a single device. single devices, regardless of how many queues they 
> may happen to have, are not reentrant, and can not deal with multiple 
> concurrent IRQ handlers poking at their registers at the same time. 
> you might have more luck with something like this 
> http://ark.intel.com/products/59062/Intel-Ethernet-Server-Adapter-I350-T2 
> but even so, I doubt it will use multiple CPU cores at the same time, 
> but it probably WILL significantly reduce the CPU overhead of dealing 
> with high volume ethernet traffic.