On Fri, 29 Jan 2021 16:35:47 +0100 Björn Töpel <bjorn.topel@xxxxxxxxx> wrote: > On Fri, 29 Jan 2021 at 16:32, Björn Töpel <bjorn.topel@xxxxxxxxx> wrote: > > > > From: Björn Töpel <bjorn.topel@xxxxxxxxx> > > > [...] > > > > For AF_XDP rxdrop this yields +600Mpps. I'll do CPU/DEVMAP > > measurements for the patch proper. > > > > Kpps, not Mpps. :-P +600Kpps from 24Mpps to 24.6Mpps I assume. This corresponds to approx 1 ns ((1/24-1/24.6)*1000 = 1.01626 ns). This also correlate with saving one function call, which is basically what the patch does. Fresh measurement "Intel(R) Xeon(R) CPU E5-1650 v4 @ 3.60GHz" with [1]: time_bench: Type:funcion_call_cost Per elem: 3 cycles(tsc) 1.053 ns time_bench: Type:func_ptr_call_cost Per elem: 4 cycles(tsc) 1.317 ns [1] https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/lib/time_bench_sample.c -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer