openvswitch+dpdk 100% cpu usage of ovs-vswitchd

Laurent Dumont laurentfdumont at
Sun Nov 8 17:04:10 UTC 2020

I have limited hands-on experience with both but they don't serve the same
purpose/have the same implementation. You use SRIOV to allow Tenants to
access the NIC cards directly and bypass any inherent linux-vr/OVS
performance limitations. This is key for NFV workloads which are expecting
large amount of PPS + low latency (because they are often just virtualized
bare-metal products with one real cloud-readiness/architecture ;) ) - This
means that a Tenant with an SRIOV port can use DPDK + access the NIC
through the VF which means (in theory) a better performance than OVS+DPDK.

You use ovs-dpdk to increase the performance of OVS based flows (so
provider networks + vxlan based internal-tenant networks).

On Sun, Nov 8, 2020 at 11:13 AM Satish Patel <satish.txt at> wrote:

>  Thanks. Just curious then why people directly go for SR-IOV
> implementation where they get better performance + they can use the
> same CPU more also. What are the measure advantages or features
> attracting the community to go with DPDK over SR-IOV?
> On Sun, Nov 8, 2020 at 10:50 AM Laurent Dumont <laurentfdumont at>
> wrote:
> >
> > As far as I know, DPDK enabled cores will show 100% usage at all times.
> >
> > On Sun, Nov 8, 2020 at 9:39 AM Satish Patel <satish.txt at>
> wrote:
> >>
> >> Folks,
> >>
> >> Recently i have added come compute nodes in cloud supporting
> >> openvswitch-dpdk for performance. I am seeing all my PMD cpu cores are
> >> 100% cpu usage on linux top command. It is normal behavior from first
> >> looks. It's very scary to see 400% cpu usage on top. Can someone
> >> confirm before I assume it's normal and what we can do to reduce it if
> >> it's too high?
> >>
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