[dpdk-dev] [PATCH v1] ixgbe_pmd: forbid tx_rs_thresh above 1 for all NICs but 82598

[Ananyev, Konstantin]

Hi Thomas,

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Thomas Monjalon
> Sent: Wednesday, September 09, 2015 1:19 PM
> To: Zhang, Helin
> Cc: dev at dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v1] ixgbe_pmd: forbid tx_rs_thresh above 1 for all NICs but 82598
> 
> 2015-08-25 20:13, Zhang, Helin:
> > Yes, I got the perfect answers. Thank you very much!
> > I just wanted to make sure the test case was OK with the limit of maximum number of descriptors, as I heard there is a hang issue on
> other NICs of using more descriptors than hardware allowed.
> > OK. I am still waiting for the answers/confirmation from x540 hardware designers. We need all agree on your patches to avoid risks.
> 
> Helin, any news?
> Can we apply v4 of this patch?

Unfortunately we are seeing a huge performance drop with that patch:
On my box bi-directional traffic (64B packet) over one port can't reach even 11 Mpps.
We are still doing some experiments and consultations with ND guys how we can overcome
this problem and keep performance intact.

Konstantin