Subject: Re: [RFC PATCH 00/24] Introducing AF_XDP support

From: Jesper Dangaard Brouer <[email-masked]>
Date: Fri, 2 Feb 2018 11:31:34 +0100

On Wed, 31 Jan 2018 14:53:32 +0100
Björn Töpel <[email-masked]> wrote:

> Below are the results in Mpps of the I40E NIC benchmark runs for 64
> byte packets, generated by commercial packet generator HW that is
> generating packets at full 40 Gbit/s line rate.
>  
> XDP baseline numbers without this RFC:
> xdp_rxq_info --action XDP_DROP 31.3 Mpps
> xdp_rxq_info --action XDP_TX   16.7 Mpps
>  
> XDP performance with this RFC i.e. with the buffer allocator:
> XDP_DROP 21.0 Mpps
> XDP_TX   11.9 Mpps
>  
> AF_PACKET V4 performance from previous RFC on 4.14-rc7:
> Benchmark   V2     V3     V4     V4+ZC
> rxdrop      0.67   0.73   0.74   33.7
> txpush      0.98   0.98   0.91   19.6
> l2fwd       0.66   0.71   0.67   15.5

My numbers from before:
        V4+ZC
rxdrop  35.2 Mpps
txpush  20.7 Mpps
l2fwd   16.9 Mpps

> AF_XDP performance:
> Benchmark   XDP_SKB   XDP_DRV    XDP_DRV_ZC (all in Mpps)
> rxdrop      3.3        11.6         16.9
> txpush      2.2         NA*         21.8
> l2fwd       1.7         NA*         10.4

The numbers on my system are better than your system, and compared to
the my-own before results, the txpush is almost the same, and the gap
between l2fwd is smaller for me.

The surprise is the drop in the 'rxdrop' performance.

        XDP_DRV_ZC
rxdrop  22.0 Mpps
txpush  20.9 Mpps
l2fwd   14.2 Mpps

BUT is also seems you have generally slowed down the XDP_DROP results
for i40e:

Before:
 sudo ./xdp_bench01_mem_access_cost --dev i40e1
 XDP_DROP     35878204   35,878,204         no_touch  

After this patchset:
 $ sudo ./xdp_bench01_mem_access_cost --dev i40e1
 XDP_action   pps        pps-human-readable mem      
 XDP_DROP     28992009   28,992,009         no_touch  

And if I read data:
 sudo ./xdp_bench01_mem_access_cost --dev i40e1 --read
 XDP_action   pps        pps-human-readable mem      
 XDP_DROP     25107793   25,107,793         read      

BTW, see you soon in Brussels (FOSDEM18) ...
-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer

$ sudo ./xdpsock --rxdrop --interface=i40e1 --queue=11
[...]
i40e1:11 rxdrop 	
                pps         pkts        60.01      
rx              22,040,099  1,322,572,352
tx              0           0          

$ sudo ./xdpsock --txonly --interface=i40e1 --queue=11
[...]
i40e1:11 txonly 	
                pps         pkts        239.03     
rx              0           0          
tx              20,937,885  5,004,790,500

$ sudo ./xdpsock --l2fwd --interface=i40e1 --queue=11
[...]
i40e1:11 l2fwd 	
                pps         pkts        152.02     
rx              14,244,719  2,165,460,044
tx              14,244,718  2,165,459,915

My before results:

 $ sudo ./bench_all.sh
 You might want to change the parameters in ./bench_all.sh
 i40e1 cpu5 duration 30s zc 16
 i40e1 v2 rxdrop    duration 29.27s rx:    62959986pkts @  2150794.94pps
 i40e1 v3 rxdrop    duration 29.18s rx:    68470248pkts @  2346658.86pps
 i40e1 v4 rxdrop    duration 29.45s rx:    68900864pkts @  2339633.99pps
 i40e1 v4 rxdrop zc duration 29.36s rx:  1033722048pkts @ 35206198.62pps

 i40e1 v2 txonly    duration 29.16s tx:  63272640pkts @     2169632.53pps.
 i40e1 v3 txonly    duration 29.14s tx:  62531968pkts @     2145714.21pps.
 i40e1 v4 txonly    duration 29.48s tx:  40587316pkts @     1376761.87pps.
 i40e1 v4 txonly zc duration 29.36s tx: 608794761pkts @    20738953.62pps.

 i40e1 v2 l2fwd    duration 29.19s rx:  57532736pkts @  1970885.56pps
                                   tx   57532672pkts @  1970883.37pps.
 i40e1 v3 l2fwd    duration 29.16s rx:  57675961pkts @  1978149.64pps
                                   tx:  57675897pkts @  1978147.44pps.
 i40e1 v4 l2fwd    duration 29.51s rx:     29732pkts @     1007.58pps
                                   tx:     28708pkts @      972.88pps.
 i40e1 v4 l2fwd zc duration 29.32s rx: 497528256pkts @ 16969091.01pps
                                   tx: 497527296pkts @ 16969058.27pps.