Re: [External] Re: [PATCH v2] sock: add tracepoint for send recv length

From: 运辉崔
Date: Thu Jan 05 2023 - 21:58:18 EST


On Thu, Jan 5, 2023 at 8:03 PM Paolo Abeni <pabeni@xxxxxxxxxx> wrote:

> > We can obtain the information with kretprobe, but as we know, kprobe gets
> > the result by trappig in an exception, which loses performance compared
> > to tracepoint. We did a test for performance comparison. The results are
> > as follows. Time per request, sock_sendmsg(k,kr): 12.382ms,
> > tcp_send_length(tracepoint): 11.887ms,without hook:11.222ms
>
> 12 ms per packet? I hope there is a an error in the unit of
> measurement.
>
> I'm unsure the delta wrt kreprobe justifies this change.
>
> In any case you need to include the netdev ML into the recipients list,
> and even Cong Wang, as he provided feedback on v1.
>
> Thanks,
>
> Paolo
>

I will add the record of testing with the tool to the commit log of
v3, and then send the email to netdev ML and CongWang, thank you.