[-- Attachment #1: Type: text/plain, Size: 537 bytes --] Hi, We have an application using DPDK on AWS and would like to port it to Azure. What would be recommended PMD to use? If I understand correctly, we can either use the Netvsc PMD or the vdev_Netvsc PMD. It seems the Netvsc PMD is newer. An alternative is to use the mlx4 PMD by only attaching to the mlx NIC's PCI address. As I understand it, the concern is the mlx nic may not receive all the packets. We run a proprietary UDP based protocol on top of DPDK. Are all UDP packets guaranteed to be received by the mlx NIC? Thanks, Yang [-- Attachment #2: Type: text/html, Size: 645 bytes --]
On Tue, 12 Apr 2022 13:09:51 -0700 Yang Luan <luan.penny@gmail.com> wrote: > Hi, > > We have an application using DPDK on AWS and would like to port it to > Azure. What would be recommended PMD to use? If I understand correctly, we > can either use the Netvsc PMD or the vdev_Netvsc PMD. It seems the Netvsc > PMD is newer. Short answer: Netvsc PMD is faster and can handle events better. vdev_netvsc/failsafe/tap is slower but can emulate some types of rte_flow. > > An alternative is to use the mlx4 PMD by only attaching to the mlx NIC's > PCI address. As I understand it, the concern is the mlx nic may not receive > all the packets. We run a proprietary UDP based protocol on top of DPDK. > Are all UDP packets guaranteed to be received by the mlx NIC? That won't work. the MLX device only sees established flows.
[-- Attachment #1: Type: text/plain, Size: 1242 bytes --] Thanks Stephen. Is the Netvsc PMD selected by default or I'll need to specify it somewhere? Since I'm running a proprietary UDP protocol, 3rd parties (e.g. Azure) won't know how a flow is established. I'm curious how exactly Azure selects which NIC to receive a given packet? Yang On Wed, Apr 13, 2022 at 8:58 AM Stephen Hemminger < stephen@networkplumber.org> wrote: > On Tue, 12 Apr 2022 13:09:51 -0700 > Yang Luan <luan.penny@gmail.com> wrote: > > > Hi, > > > > We have an application using DPDK on AWS and would like to port it to > > Azure. What would be recommended PMD to use? If I understand correctly, > we > > can either use the Netvsc PMD or the vdev_Netvsc PMD. It seems the Netvsc > > PMD is newer. > > Short answer: > > Netvsc PMD is faster and can handle events better. > vdev_netvsc/failsafe/tap is slower but can emulate some types of rte_flow. > > > > > An alternative is to use the mlx4 PMD by only attaching to the mlx NIC's > > PCI address. As I understand it, the concern is the mlx nic may not > receive > > all the packets. We run a proprietary UDP based protocol on top of DPDK. > > Are all UDP packets guaranteed to be received by the mlx NIC? > > That won't work. the MLX device only sees established flows. > [-- Attachment #2: Type: text/html, Size: 1787 bytes --]
On Wed, 13 Apr 2022 11:41:30 -0700
Yang Luan <luan.penny@gmail.com> wrote:
> Thanks Stephen.
>
> Is the Netvsc PMD selected by default or I'll need to specify it somewhere?
>
> Since I'm running a proprietary UDP protocol, 3rd parties (e.g. Azure)
> won't know how a flow is established. I'm curious how exactly Azure selects
> which NIC to receive a given packet?
>
> Yang
>
> On Wed, Apr 13, 2022 at 8:58 AM Stephen Hemminger <
> stephen@networkplumber.org> wrote:
>
> > On Tue, 12 Apr 2022 13:09:51 -0700
> > Yang Luan <luan.penny@gmail.com> wrote:
> >
> > > Hi,
> > >
> > > We have an application using DPDK on AWS and would like to port it to
> > > Azure. What would be recommended PMD to use? If I understand correctly,
> > we
> > > can either use the Netvsc PMD or the vdev_Netvsc PMD. It seems the Netvsc
> > > PMD is newer.
> >
> > Short answer:
> >
> > Netvsc PMD is faster and can handle events better.
> > vdev_netvsc/failsafe/tap is slower but can emulate some types of rte_flow.
> >
> > >
> > > An alternative is to use the mlx4 PMD by only attaching to the mlx NIC's
> > > PCI address. As I understand it, the concern is the mlx nic may not
> > receive
> > > all the packets. We run a proprietary UDP based protocol on top of DPDK.
> > > Are all UDP packets guaranteed to be received by the mlx NIC?
> >
> > That won't work. the MLX device only sees established flows.
> >
The choice is made based on whether vmbus is unbound from kernel or not.
If vmbus is left bound to kernel, then hv_netvsc will look at all the network
devices, and those without any routes it will setup. The setup makes the
TAP/failsafe sub devices.
If vmbus device is unbound from network device and instead bound to hv_uio_generic,
then the DPDK startup code will see it and should setup from there.
The documentation is there in many places.