Hi Liping, Thank you for your reply,
We notice packet drops during high load, I did try txqueue and didn't help so I believe I am going to try miltiqueue. For SRIOV I have to look if I have support in my nic. We are using queens so I think queue size option not possible :( We are using voip application and traffic is udp so our pps rate is 60k to 80k per vm instance. I will share my result as soon as I try multiqueue. Sent from my iPhone > On Sep 16, 2018, at 2:27 AM, Liping Mao (limao) <li...@cisco.com> wrote: > > Hi Satish, > > > > Did your packet loss happen always or it only happened when heavy load? > > AFAIK, if you do not tun anything, the vm tap can process about 50kpps before > the tap device start to drop packets. > > > > If it happened in heavy load, couple of things you can try: > > 1) increase tap queue length, usually the default value is 500, you can try > larger. (seems like you already tried) > > 2) Try to use virtio multi queues feature , see [1]. Virtio use one queue for > rx/tx in vm, with this feature you can get more queues. You can check > > 3) In rock version, you can use [2] to increase virtio queue size, the > default queues size is 256/512, you may increase it to 1024, this would help > to increase pps of the tap device. > > > > If all these things can not get your network performance requirement, you may > need to move to use dpdk / sriov stuff to get more vm performance. > > I did not actually used them in our env, you may refer to [3] > > > > [1] > https://specs.openstack.org/openstack/nova-specs/specs/liberty/implemented/libvirt-virtiomq.html > > [2] > https://specs.openstack.org/openstack/nova-specs/specs/rocky/implemented/libvirt-virtio-set-queue-sizes.html > > [3] https://docs.openstack.org/ocata/networking-guide/config-sriov.html > > > > Regards, > > Liping Mao > > > > 在 2018/9/16 13:07，“Satish Patel”<satish....@gmail.com> 写入: > > > > [root@compute-33 ~]# ifconfig tap5af7f525-5f | grep -i drop > > RX errors 0 dropped 0 overruns 0 frame 0 > > TX errors 0 dropped 2528788837 overruns 0 carrier 0 collisions 0 > > > > Noticed tap interface dropping TX packets and even after increasing > > txqueue from 1000 to 10000 nothing changed, still getting packet > > drops. > > > >> On Sat, Sep 15, 2018 at 4:22 PM Satish Patel <satish....@gmail.com> wrote: >> >> > >> Folks, > >> > >> I need some advice or suggestion to find out what is going on with my > >> network, we have notice high packet loss on openstack instance and not > >> sure what is going on, same time if i check on host machine and it has > >> zero packet loss.. this is what i did for test... > >> > >> ping 8.8.8.8 > >> > >> from instance: 50% packet loss > >> from compute host: 0% packet loss > >> > >> I have disabled TSO/GSO/SG setting on physical compute node but still > >> getting packet loss. > >> > >> We have 10G NIC on our network, look like something related to tap > >> interface setting.. > > > > _______________________________________________ > > Mailing list: http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > Post to : openstack@lists.openstack.org > > Unsubscribe : http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > > _______________________________________________ Mailing list: http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack Post to : openstack@lists.openstack.org Unsubscribe : http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack
