From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yerden Zhumabekov <e_zhumabekov@sts.kz>
Subject: Re: pcap->eth low TX performance
Date: Mon, 7 Sep 2015 08:40:59 +0600
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 <CAMFWN9n4hfTgBLpZKdU5j=q_wE4nkXdjY-cT3MeBnXMPhTLTeA@mail.gmail.com>
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To: Kyle Larose <eomereadig@gmail.com>
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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 =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
> 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 ap=
p
>     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 dr=
op
>     while trying to send those packets over the Ethernet device. I trie=
d
>     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
>
>

--=20
Sincerely,

Yerden Zhumabekov
State Technical Service
Astana, KZ