[dpdk-dev] Performance hit - NICs on different CPU sockets

Take Ceara dumitru.ceara at gmail.com
Thu Jun 16 17:16:10 CEST 2016


On Thu, Jun 16, 2016 at 4:58 PM, Wiles, Keith <keith.wiles at intel.com> wrote:
>
> From the output below it appears the x710 devices 01:00.[0-3] are on socket 0
> And the x710 devices 02:00.[0-3] sit on socket 1.
>

I assume there's a mistake here. The x710 devices on socket 0 are:
$ lspci | grep -ie "01:.*x710"
01:00.0 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)
01:00.1 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)
01:00.2 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)
01:00.3 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)

and the X710 devices on socket 1 are:
$ lspci | grep -ie "81:.*x710"
81:00.0 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)
81:00.1 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)
81:00.2 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)
81:00.3 Ethernet controller: Intel Corporation Ethernet Controller
X710 for 10GbE SFP+ (rev 01)

> This means the ports on 01.00.xx should be handled by socket 0 CPUs and 02:00.xx should be handled by Socket 1. I can not tell if that is the case for you here. The CPUs or lcores from the cpu_layout.py should help understand the layout.
>

That was the first scenario I tried:
- assign 16 CPUs from socket 0 to port 0 (01:00.3)
- assign 16 CPUs from socket 1 to port 1 (81:00.3)

Our performance measurements show then a setup rate of 1.6M sess/s
which is less then half of what I get when i install both X710 on
socket 1 and use only 16 CPUs from socket 1 for both ports.

I double checked the cpu layout. We also have our own CLI and warnings
when using cores that are not on the same socket as the port they're
assigned too so the mapping should be fine.

Thanks,
Dumitru


More information about the dev mailing list