On 16-04-08 12:48 AM, Brenden Blanco wrote:
Add a sample program that only drops packets at the
BPF_PROG_TYPE_PHYS_DEV hook of a link. With the drop-only program,
observed single core rate is ~19.5Mpps.
Other tests were run, for instance without the dropcnt increment or
without reading from the packet header, the packet rate was mostly
unchanged.
$ perf record -a samples/bpf/netdrvx1 $(</sys/class/net/eth0/ifindex)
proto 17: 19596362 drops/s
./pktgen_sample03_burst_single_flow.sh -i $DEV -d $IP -m $MAC -t 4
Running... ctrl^C to stop
Device: eth4@0
Result: OK: 7873817(c7872245+d1572) usec, 38801823 (60byte,0frags)
4927955pps 2365Mb/sec (2365418400bps) errors: 0
Device: eth4@1
Result: OK: 7873817(c7872123+d1693) usec, 38587342 (60byte,0frags)
4900715pps 2352Mb/sec (2352343200bps) errors: 0
Device: eth4@2
Result: OK: 7873817(c7870929+d2888) usec, 38718848 (60byte,0frags)
4917417pps 2360Mb/sec (2360360160bps) errors: 0
Device: eth4@3
Result: OK: 7873818(c7872193+d1625) usec, 38796346 (60byte,0frags)
4927259pps 2365Mb/sec (2365084320bps) errors: 0
perf report --no-children:
29.48% ksoftirqd/6 [mlx4_en] [k] mlx4_en_process_rx_cq
18.17% ksoftirqd/6 [mlx4_en] [k] mlx4_en_alloc_frags
8.19% ksoftirqd/6 [mlx4_en] [k] mlx4_en_free_frag
5.35% ksoftirqd/6 [kernel.vmlinux] [k] get_page_from_freelist
2.92% ksoftirqd/6 [kernel.vmlinux] [k] free_pages_prepare
2.90% ksoftirqd/6 [mlx4_en] [k] mlx4_call_bpf
2.72% ksoftirqd/6 [fjes] [k] 0x000000000000af66
2.37% ksoftirqd/6 [kernel.vmlinux] [k] swiotlb_sync_single_for_cpu
1.92% ksoftirqd/6 [kernel.vmlinux] [k] percpu_array_map_lookup_elem
1.83% ksoftirqd/6 [kernel.vmlinux] [k] free_one_page
1.70% ksoftirqd/6 [kernel.vmlinux] [k] swiotlb_sync_single
1.69% ksoftirqd/6 [kernel.vmlinux] [k] bpf_map_lookup_elem
1.33% swapper [kernel.vmlinux] [k] intel_idle
1.32% ksoftirqd/6 [fjes] [k] 0x000000000000af90
1.21% ksoftirqd/6 [kernel.vmlinux] [k] sk_load_byte_positive_offset
1.07% ksoftirqd/6 [kernel.vmlinux] [k] __alloc_pages_nodemask
0.89% ksoftirqd/6 [kernel.vmlinux] [k] __rmqueue
0.84% ksoftirqd/6 [mlx4_en] [k] mlx4_alloc_pages.isra.23
0.79% ksoftirqd/6 [kernel.vmlinux] [k] net_rx_action
machine specs:
receiver - Intel E5-1630 v3 @ 3.70GHz
sender - Intel E5645 @ 2.40GHz
Mellanox ConnectX-3 @40G
Ok, sorry - should have looked this far before sending earlier email.
So when you run concurently you see about 5Mpps per core but if you
shoot all traffic at a single core you see 20Mpps?
Devil's advocate question:
If the bottleneck is the driver - is there an advantage in adding the
bpf code at all in the driver?
I am curious than before to see the comparison for the same bpf code
running at tc level vs in the driver..
cheers,
jamal
