possible macvlan packet loss

possible macvlan packet loss

[Aleksander Dutkowski]

Hello,

we are experiencing something, that seems to be packet loss on macvlan
interface.
Input is ~350Mbps of multicasts, scattered over 120 docker containers,
each having macvlan on top of the same mellanox 10G NIC. Each of
macvlans have bcqueuelen set to INT_MAX.
Streams recorded from phys interface have all packets, whereas streams
recorded from macvlan have drops.

I wonder what is the best way to test and measure the queue fulfillment?
We can do simple printf when the queue is full, but maybe there are
some tools or techniques I'm not aware of that we can use?

Thanks
Alex

Re: possible macvlan packet loss

[Vadim Fedorenko]

On 24.01.2023 15:14, Aleksander Dutkowski wrote:
> Hello,
> 
> we are experiencing something, that seems to be packet loss on macvlan
> interface.
> Input is ~350Mbps of multicasts, scattered over 120 docker containers,
> each having macvlan on top of the same mellanox 10G NIC. Each of
> macvlans have bcqueuelen set to INT_MAX.
> Streams recorded from phys interface have all packets, whereas streams
> recorded from macvlan have drops.
> 
Is it real packet loss or just reordering of the packets that is accounted by 
the software as a loss?

> I wonder what is the best way to test and measure the queue fulfillment?
> We can do simple printf when the queue is full, but maybe there are
> some tools or techniques I'm not aware of that we can use?
> 
> Thanks
> Alex

Re: possible macvlan packet loss

[Jakub Kicinski]

On Tue, 24 Jan 2023 16:14:03 +0100 Aleksander Dutkowski wrote:
> I wonder what is the best way to test and measure the queue fulfillment?
> We can do simple printf when the queue is full, but maybe there are
> some tools or techniques I'm not aware of that we can use?

In terms of debugging tools bpftrace (potentially combined with kprobes)
will change your life.