[dpdk-dev] pcap->eth low TX performance

[dpdk-dev] pcap->eth low TX performance

[Yerden Zhumabekov]

Hello,

Did anyone try to work with pcap PMD recently? We're testing our app
with this setup:

PCAP --- rte_eth_rx_burst--> APP-> rte_eth_tx_burst -> ethdev

I'm experiencing very low TX performance leading to massive mbuf drop
while trying to send those packets over the Ethernet device. I tried
running ordinary l2fwd and got the same issue with over 80-90% of
packets drop. When I substitute PCAP with another ordinary Ethernet
device, everything works fine. Can anyone share an idea?

-- 
Sincerely,

Yerden Zhumabekov
State Technical Service
Astana, KZ

Re: [dpdk-dev] pcap->eth low TX performance

[Kyle Larose]

Are you reading from the pcap faster than the device can transmit? Does the
app hold off reading from the pcap when the ethdev is pushing back, or does
it just tail drop?

On Fri, Sep 4, 2015 at 12:14 AM, Yerden Zhumabekov <e_zhumabekov@sts.kz>
wrote:

> Hello,
>
> Did anyone try to work with pcap PMD recently? We're testing our app
> with this setup:
>
> PCAP --- rte_eth_rx_burst--> APP-> rte_eth_tx_burst -> ethdev
>
> I'm experiencing very low TX performance leading to massive mbuf drop
> while trying to send those packets over the Ethernet device. I tried
> running ordinary l2fwd and got the same issue with over 80-90% of
> packets drop. When I substitute PCAP with another ordinary Ethernet
> device, everything works fine. Can anyone share an idea?
>
> --
> Sincerely,
>
> Yerden Zhumabekov
> State Technical Service
> Astana, KZ
>
>

Re: [dpdk-dev] pcap->eth low TX performance

[Yerden Zhumabekov]

tx burst sends, say, 10-15% percent of a supplied array. The tail is
being ignored so I have to drop it to avoid overflow.
Ethernet device is 82599.

In my app, I transmit all traffic through a ring then feed it to eth.
That leads to overflow as well.

04.09.2015 20:03, Kyle Larose пишет:
> Are you reading from the pcap faster than the device can transmit?
> Does the app hold off reading from the pcap when the ethdev is pushing
> back, or does it just tail drop?
>
> On Fri, Sep 4, 2015 at 12:14 AM, Yerden Zhumabekov
> <e_zhumabekov@sts.kz <mailto:e_zhumabekov@sts.kz>> wrote:
>
>     Hello,
>
>     Did anyone try to work with pcap PMD recently? We're testing our app
>     with this setup:
>
>     PCAP --- rte_eth_rx_burst--> APP-> rte_eth_tx_burst -> ethdev
>
>     I'm experiencing very low TX performance leading to massive mbuf drop
>     while trying to send those packets over the Ethernet device. I tried
>     running ordinary l2fwd and got the same issue with over 80-90% of
>     packets drop. When I substitute PCAP with another ordinary Ethernet
>     device, everything works fine. Can anyone share an idea?
>
>     --
>     Sincerely,
>
>     Yerden Zhumabekov
>     State Technical Service
>     Astana, KZ
>
>

-- 
Sincerely,

Yerden Zhumabekov
State Technical Service
Astana, KZ