[dpdk-dev] DPDK 17.02 RC-3 performance degradation of ~10%

[De Lara Guarch, Pablo]

Hi,

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Thomas Monjalon
> Sent: Tuesday, February 14, 2017 1:05 PM
> To: Hanoch Haim (hhaim)
> Cc: dev at dpdk.org; Mcnamara, John; Ido Barnea (ibarnea)
> Subject: Re: [dpdk-dev] DPDK 17.02 RC-3 performance degradation of ~10%
> 
> 2017-02-14 12:19, Mcnamara, John:
> > From: Hanoch Haim (hhaim)
> > > We (trex traffic generator project) upgrade DPDK version from 16.07 to
> > > 17.02arc-3 and we experienced a performance degradation on the
> following
> > > NICS:
> [...]
> >
> > Could you do a git-bisect to identify the change that caused this?
> 
> +1 for the bisect.
> Please could you try to isolate the change causing the regression?

I reproduced the regression for i40e driver (3-4% degradation, not 10%). The commit that caused it was the following:
5ea0942129a4 ("net/i40e: add packet type metadata in vector Rx")

This commit was introduced in 16.11, and not in 17.02. This caused some performance degradation
in the i40e vector RX, due to the addition of packet type parsing in the PMD.

Thanks,
Pablo