Re: [dpdk-users] Mellanox ConnectX-4, DPDK and extreme latency issues

[Adrien Mazarguil <adrien.mazarguil@6wind.com>]

Arjun,

On Thu, Jun 29, 2017 at 05:26:02AM +0000, Shahaf Shuler wrote:
> Hi Arjun,
> 
> Thursday, June 22, 2017 9:40 PM, Arjun Roy,
> > 
> > Greetings all.
> > 
> > I have a weird issue regarding excessive latency using Mellanox ConnectX-4
> > 100Gbe cards, DPDK and packet forwarding. Specifically: running the l3fwd
> > and basicfwd DPDK example programs yields ping latencies of several (5-8)
> > milliseconds. I tried the same test using an Intel X-540 AT2 card on the same
> > systems and the latency was on the order of 4-5 microseconds.
> 
> Thanks for reporting.
> This is the first time we hit such scenario, we will check it internally and will get back to you with answers. 

Back to this topic, could it be the same issue as reported by Sagi,
"mlx5 high latency observed on send operations" [1]?

The related patches have been submitted and are on track for DPDK 17.11.
While they are not yet on the master tree, you can find them on
dpdk-next-net.

[1] http://dpdk.org/ml/archives/dev/2017-August/073081.html

-- 
Adrien Mazarguil
6WIND