[dpdk-users] Howto control sending IFG

[VERDOUX, Sylvain]

Thank you both for the link to moongen, i did not see it during my research and it seems the project is exactly studying what I'm facing. Moongen in its software solution is filling gaps sending invalid packets. I'm not sure I can go with that solution but it is worth testing.

Best Regards,

Sylvain

-----Message d'origine-----
De : Van Haaren, Harry [mailto:harry.van.haaren at intel.com] 
Envoyé : mardi 15 novembre 2016 16:11
À : VERDOUX, Sylvain; users at dpdk.org
Objet : RE: Howto control sending IFG

> From: users [mailto:users-bounces at dpdk.org] On Behalf Of VERDOUX, 
> Sylvain
> Sent: Tuesday, November 15, 2016 2:31 PM
> To: users at dpdk.org
> Subject: [dpdk-users] Howto control sending IFG
> 
> Hi,
> 
> Using i40e pmd i'm currently trying to control precisely packets 
> emission rate. When dealing with an IFG (inter frame gap) of 1ms it 
> works fine, but dealing with IFG under 100us I'm seeing bursts on the 
> receiver. I was wondering if there was a better way to be close to the 
> wanted IFG instead of waiting and using rte_eth_tx_burst with 1 packet 
> at a time. I did not see anything relevant in mbuf structure, and I was wondering if tx queue threshold could help, but I'm not sure to understand well the impact of those thresholds.
> Any advice is welcome :)
> 
> Best Regards,
> Sylvain


Hi Sylvain,

I don't personally have experience, however the MoonGen traffic generator has a few solutions to this problem; I can recommend reading their documentation on rate control[1], and the paper they wrote on the topic[2].

Hopefully that leads you to a solution, -Harry

[1] https://github.com/emmericp/MoonGen#rate-control
[2] https://www.net.in.tum.de/fileadmin/bibtex/publications/papers/MoonGen_IMC2015.pdf