Re: [PATCH net-next] net/mlx5e: Prefetch packets of upcoming CQEs in the linear MPWQE path

[Alexei Starovoitov]

On Wed Nov 4, 2026 at 7:46 PM UTC, Antonio Quartulli wrote:
> Hi Alexei,
>
> thank you very much for the review!!
>
> On 04/11/2026 01:39, Alexei Starovoitov wrote:
>> can we prefetch 4 strides ahead without the CQE, like gve_rx() ?
>
> Yep! I measured your version against this patch on the same system (one
> RX queue, MTU 1500, mean of 3 runs, gain over stock):
>
>                                     v1      yours    yours + shinfo
>    UDP 512B flood, packets/s       +39%      +35%      +36%
>    TCP, 1 stream                    +7%       +5%       +8%
>    TCP in an ovpn UDP tunnel       +36%       +4%      +34%
>    XDP_DROP reading the packet,
>      NAPI CPU cycles/packet        -38%      -45%      -32%
>    XDP_TX, cycles/packet           -35%      -30%      -33%
>
>
> It matches my v1, except where every packet becomes its own skb, like the
> records of a VPN tunnel (ovpn from a development tree here).
> In that case I got only +4% instead of +36%.
> Dropping only the skb_shared_info prefetch from v1 gives +5% there, so
> that line is the one that matters.

Thanks for the benchmarks. Glad it helped.