On Thu, 22 Jun 2017 15:01:22 +0200
Paolo Abeni <pab...@redhat.com> wrote:
> very similar to commit dd99e425be23 ("udp: prefetch
> rmem_alloc in udp_queue_rcv_skb()"), this allows saving a cache
> miss when the BH is bottle-neck for UDP over ipv6 packet
> processing, e.g. for small packets when a single RX NIC ingress
> queue is in use.
>
> Performances under flood when multiple NIC RX queues used are
> unaffected, but when a single NIC rx queue is in use, this
> gives ~8% performance improvement.
>
> Signed-off-by: Paolo Abeni <pab...@redhat.com>
Testing IPv4 UDP on top of this patch, with ip_early_demux enabled.
I'm impressed, we can now to almost 3 Mpps UDP (across two CPUs) :-)))
Last time I tested on this machine it was around 2.3Mpps.
Good work Paolo! :-)
[jbrouer@skylake src]$ sysctl net/ipv4/ip_early_demux=1
net.ipv4.ip_early_demux = 1
[jbrouer@skylake src]$
[jbrouer@skylake src]$ sudo taskset -c 2 ./udp_sink --port 9 --count $((10**6))
--repeat 1000 --recvmsg --connect
run count ns/pkt pps cycles payload
recvmsg run: 0 1000000 341.62 2927192.65 1369 18
demux:1 c:1
recvmsg run: 1 1000000 350.81 2850569.36 1406 18
demux:1 c:1
recvmsg run: 2 1000000 352.18 2839478.74 1411 18
demux:1 c:1
recvmsg run: 3 1000000 341.43 2928871.10 1368 18
demux:1 c:1
recvmsg run: 4 1000000 350.65 2851810.35 1405 18
demux:1 c:1
recvmsg run: 5 1000000 350.91 2849751.29 1406 18
demux:1 c:1
recvmsg run: 6 1000000 342.68 2918138.00 1373 18
demux:1 c:1
recvmsg run: 7 1000000 351.37 2845969.40 1408 18
demux:1 c:1
recvmsg run: 8 1000000 351.07 2848452.09 1407 18
demux:1 c:1
https://github.com/netoptimizer/network-testing/blob/master/src/udp_sink.c
--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer
