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Oh. I heard from someone on the reddit said that Ovs-dpdk is transparent
with user?

So It’s not correct?

On Thu, 7 Sep 2023 at 22:13 Satish Patel <satish.txt at gmail.com> wrote:

> Because DPDK required DPDK support inside guest VM. It's not suitable for
> general purpose workload. You need your guest VM network to support DPDK to
> get 100% throughput.
>
> On Thu, Sep 7, 2023 at 8:06 AM Ha Noi <hanoi952022 at gmail.com> wrote:
>
>> Hi Satish,
>>
>> Why dont you use DPDK?
>>
>> Thanks
>>
>> On Thu, 7 Sep 2023 at 19:03 Satish Patel <satish.txt at gmail.com> wrote:
>>
>>> I totally agreed with Sean on all his points but trust me, I have tried
>>> everything possible to tune OS, Network stack, multi-queue, NUMA, CPU
>>> pinning and name it.. but I didn't get any significant improvement. You may
>>> gain 2 to 5% gain with all those tweek. I am running the entire workload on
>>> sriov and life is happy except no LACP bonding.
>>>
>>> I am very interesting is this project
>>> https://docs.openvswitch.org/en/latest/intro/install/afxdp/
>>>
>>> On Thu, Sep 7, 2023 at 6:07 AM Ha Noi <hanoi952022 at gmail.com> wrote:
>>>
>>>> Dear Smoney,
>>>>
>>>>
>>>>
>>>> On Thu, Sep 7, 2023 at 12:41 AM <smooney at redhat.com> wrote:
>>>>
>>>>> On Wed, 2023-09-06 at 11:43 -0400, Satish Patel wrote:
>>>>> > Damn! We have noticed the same issue around 40k to 55k PPS. Trust me
>>>>> > nothing is wrong in your config. This is just a limitation of the
>>>>> software
>>>>> > stack and kernel itself.
>>>>> its partly determined by your cpu frequency.
>>>>> kernel ovs of yesteryear could handel about 1mpps total on a ~4GHZ
>>>>> cpu. with per port troughpuyt being lower dependin on what qos/firewall
>>>>> rules that were apllied.
>>>>>
>>>>>
>>>>
>>>> My CPU frequency is 3Ghz and using CPU Intel Gold 2nd generation. I
>>>> think the problem is tuning in the compute node inside. But I cannot find
>>>> any guide or best practices for it.
>>>>
>>>>
>>>>
>>>>> moving form iptables firewall to ovs firewall can help to some degree
>>>>> but your partly trading connection setup time for statead state
>>>>> troughput
>>>>> with the overhead of the connection tracker in ovs.
>>>>>
>>>>> using stateless security groups can help
>>>>>
>>>>> we also recently fixed a regression cause by changes in newer versions
>>>>> of ovs.
>>>>> this was notable in goign form rhel 8 to rhel 9 where litrally it
>>>>> reduced
>>>>> small packet performce to 1/10th and jumboframes to about 1/2
>>>>> on master we have a config option that will set the default qos on a
>>>>> port to linux-noop
>>>>>
>>>>> https://github.com/openstack/os-vif/blob/master/vif_plug_ovs/ovs.py#L106-L125
>>>>>
>>>>> the backports are propsoed upstream
>>>>> https://review.opendev.org/q/Id9ef7074634a0f23d67a4401fa8fca363b51bb43
>>>>> and we have backported this downstream to adress that performance
>>>>> regression.
>>>>> the upstram backport is semi stalled just ebcasue we wanted to disucss
>>>>> if we shoudl make ti opt in
>>>>> by default upstream while backporting but it might be helpful for you
>>>>> if this is related to yoru current
>>>>> issues.
>>>>>
>>>>> 40-55 kpps is kind of low for kernel ovs but if you have a low
>>>>> clockrate cpu, hybrid_plug + incorrect qos
>>>>> then i could see you hitting such a bottelneck.
>>>>>
>>>>> one workaround by the way without the os-vif workaround backported is
>>>>> to set
>>>>> /proc/sys/net/core/default_qdisc to not apply any qos or a low
>>>>> overhead qos type
>>>>> i.e. sudo sysctl -w net.core.default_qdisc=pfifo_fast
>>>>>
>>>>>
>>>>
>>>>> that may or may not help but i would ensure that your are not usign
>>>>> somting like fqdel or cake
>>>>> for net.core.default_qdisc and if you are try changing it to
>>>>> pfifo_fast and see if that helps.
>>>>>
>>>>> there isnet much you can do about the cpu clock rate but ^ is
>>>>> somethign you can try for free
>>>>> note it wont actully take effect on an exsitng vm if you jsut change
>>>>> the default but you can use
>>>>> tc to also chagne the qdisk for testing. hard rebooting the vm shoudl
>>>>> also make the default take effect.
>>>>>
>>>>> the only other advice i can give assuming kernel ovs is the only
>>>>> option you have is
>>>>>
>>>>> to look at
>>>>>
>>>>> https://docs.openstack.org/nova/latest/configuration/config.html#libvirt.rx_queue_size
>>>>>
>>>>> https://docs.openstack.org/nova/latest/configuration/config.html#libvirt.tx_queue_size
>>>>> and
>>>>>
>>>>> https://docs.openstack.org/nova/latest/configuration/extra-specs.html#hw:vif_multiqueue_enabled
>>>>>
>>>>> if the bottelneck is actully in qemu or the guest kernel rather then
>>>>> ovs adjusting the rx/tx queue size and
>>>>> using multi queue can help. it will have no effect if ovs is the
>>>>> bottel neck.
>>>>>
>>>>>
>>>>>
>>>> I have set this option to 1024, and enable multiqueue as well. But it
>>>> did not help.
>>>>
>>>>
>>>>> >
>>>>> > On Wed, Sep 6, 2023 at 9:21 AM Ha Noi <hanoi952022 at gmail.com> wrote:
>>>>> >
>>>>> > > Hi Satish,
>>>>> > >
>>>>> > > Actually, our customer get this issue when the tx/rx above only
>>>>> 40k pps.
>>>>> > > So what is the threshold of this throughput for OvS?
>>>>> > >
>>>>> > >
>>>>> > > Thanks and regards
>>>>> > >
>>>>> > > On Wed, 6 Sep 2023 at 20:19 Satish Patel <satish.txt at gmail.com>
>>>>> wrote:
>>>>> > >
>>>>> > > > Hi,
>>>>> > > >
>>>>> > > > This is normal because OVS or LinuxBridge wire up VMs using TAP
>>>>> interface
>>>>> > > > which runs on kernel space and that drives higher interrupt and
>>>>> that makes
>>>>> > > > the kernel so busy working on handling packets. Standard
>>>>> OVS/LinuxBridge
>>>>> > > > are not meant for higher PPS.
>>>>> > > >
>>>>> > > > If you want to handle higher PPS then look for DPDK or SRIOV
>>>>> deployment.
>>>>> > > > ( We are running everything in SRIOV because of high PPS
>>>>> requirement)
>>>>> > > >
>>>>> > > > On Tue, Sep 5, 2023 at 11:11 AM Ha Noi <hanoi952022 at gmail.com>
>>>>> wrote:
>>>>> > > >
>>>>> > > > > Hi everyone,
>>>>> > > > >
>>>>> > > > > I'm using Openstack Train and Openvswitch for ML2 driver and
>>>>> GRE for
>>>>> > > > > tunnel type. I tested our network performance between two VMs
>>>>> and suffer
>>>>> > > > > packet loss as below.
>>>>> > > > >
>>>>> > > > > VM1: IP: 10.20.1.206
>>>>> > > > >
>>>>> > > > > VM2: IP: 10.20.1.154 <https://10.20.1.154/24>
>>>>> > > > >
>>>>> > > > > VM3: IP: 10.20.1.72
>>>>> > > > >
>>>>> > > > >
>>>>> > > > > Using iperf3 to testing performance between VM1 and VM2.
>>>>> > > > >
>>>>> > > > > Run iperf3 client and server on both VMs.
>>>>> > > > >
>>>>> > > > > On VM2: iperf3 -t 10000 -b 130M -l 442 -P 6 -u -c 10.20.1.206
>>>>> > > > >
>>>>> > > > > On VM1: iperf3 -t 10000 -b 130M -l 442 -P 6 -u -c 10.20.1.154
>>>>> > > > > <https://10.20.1.154/24>
>>>>> > > > >
>>>>> > > > >
>>>>> > > > > Using VM3 ping into VM1, then the packet is lost and the
>>>>> latency is
>>>>> > > > > quite high.
>>>>> > > > >
>>>>> > > > >
>>>>> > > > > ping -i 0.1 10.20.1.206
>>>>> > > > >
>>>>> > > > > PING 10.20.1.206 (10.20.1.206) 56(84) bytes of data.
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=1 ttl=64 time=7.70 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=2 ttl=64 time=6.90 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=3 ttl=64 time=7.71 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=4 ttl=64 time=7.98 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=6 ttl=64 time=8.58 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=7 ttl=64 time=8.34 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=8 ttl=64 time=8.09 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=10 ttl=64 time=4.57 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=11 ttl=64 time=8.74 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=12 ttl=64 time=9.37 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=14 ttl=64 time=9.59 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=15 ttl=64 time=7.97 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=16 ttl=64 time=8.72 ms
>>>>> > > > >
>>>>> > > > > 64 bytes from 10.20.1.206: icmp_seq=17 ttl=64 time=9.23 ms
>>>>> > > > >
>>>>> > > > > ^C
>>>>> > > > >
>>>>> > > > > --- 10.20.1.206 ping statistics ---
>>>>> > > > >
>>>>> > > > > 34 packets transmitted, 28 received, 17.6471% packet loss,
>>>>> time 3328ms
>>>>> > > > >
>>>>> > > > > rtt min/avg/max/mdev = 1.396/6.266/9.590/2.805 ms
>>>>> > > > >
>>>>> > > > >
>>>>> > > > >
>>>>> > > > > Does any one get this issue ?
>>>>> > > > >
>>>>> > > > > Please help me. Thanks
>>>>> > > > >
>>>>> > > >
>>>>>
>>>>>
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