> -----Original Message----- > From: Jesper Dangaard Brouer [mailto:bro...@redhat.com] > Sent: Thursday, April 12, 2018 1:05 PM > To: Björn Töpel <bjorn.to...@gmail.com> > Cc: Karlsson, Magnus <magnus.karls...@intel.com>; Duyck, Alexander H > <alexander.h.du...@intel.com>; alexander.du...@gmail.com; > john.fastab...@gmail.com; a...@fb.com; > willemdebruijn.ker...@gmail.com; dan...@iogearbox.net; > netdev@vger.kernel.org; michael.lundkv...@ericsson.com; Brandeburg, > Jesse <jesse.brandeb...@intel.com>; Singhai, Anjali > <anjali.sing...@intel.com>; Zhang, Qi Z <qi.z.zh...@intel.com>; > ravineet.si...@ericsson.com; Topel, Bjorn <bjorn.to...@intel.com>; > bro...@redhat.com > Subject: Re: [RFC PATCH v2 14/14] samples/bpf: sample application for > AF_XDP sockets > > On Tue, 27 Mar 2018 18:59:19 +0200 > Björn Töpel <bjorn.to...@gmail.com> wrote: > > > +static void dump_stats(void) > > +{ > > + unsigned long stop_time = get_nsecs(); > > + long dt = stop_time - start_time; > > + int i; > > + > > + for (i = 0; i < num_socks; i++) { > > + double rx_pps = xsks[i]->rx_npkts * 1000000000. > / dt; > > + double tx_pps = xsks[i]->tx_npkts * 1000000000. > / dt; > > + char *fmt = "%-15s %'-11.0f %'-11lu\n"; > > + > > + printf("\n sock%d@", i); > > + print_benchmark(false); > > + printf("\n"); > > + > > + printf("%-15s %-11s %-11s %-11.2f\n", "", "pps", > "pkts", > > + dt / 1000000000.); > > + printf(fmt, "rx", rx_pps, xsks[i]->rx_npkts); > > + printf(fmt, "tx", tx_pps, xsks[i]->tx_npkts); > > + } > > +} > > + > > +static void *poller(void *arg) > > +{ > > + (void)arg; > > + for (;;) { > > + sleep(1); > > + dump_stats(); > > + } > > + > > + return NULL; > > +} > > You are printing the "pps" (packets per sec) as an average over the entire > test run... could you please change that to, at least also, have an more > up-to- > date value like between the last measurement? > > The problem is that when you start the test, the first reading will be too > low, > and it takes time to average out/up. For ixgbe, first reading will be zero, > because it does a link-down+up, which stops my pktgen. > > The second annoyance is that I like to change system/kernel setting during > the run, and observe the effect. E.g change CPU sleep states (via tuned- > adm) during the test-run to see the effect, which I cannot with this long > average.
Good points. Will fix. /Magnus > > -- > Best regards, > Jesper Dangaard Brouer > MSc.CS, Principal Kernel Engineer at Red Hat > LinkedIn: http://www.linkedin.com/in/brouer
