From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: bnx2 udp multicast packet loss and jtter
Date: Fri, 17 Jun 2011 17:30:41 +0200
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To: Kieran Kunhya <kierank@ob-encoder.com>
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Le samedi 11 juin 2011 =C3=A0 15:32 +0100, Kieran Kunhya a =C3=A9crit :
> Hello,
>=20
> I get some bad packet loss and high jitter on a BCM5709. This is on
> kernel 2.6.38-8 - unfortunately using a newer kernel isn't an option
> right now.
> The bnx2 driver is version v2.0.23b.
>=20
> I've tried a lot of kenel types such as -lowlatency, -ck and vanilla.
> The thread doing the udp output is at realtime priority and the same
> thing happens with different applications.
>=20
> Example of jitter
> http://dl.dropbox.com/u/2701213/jitter.png
>=20
> Is there anything I can do to further diagnose this problem?
>=20

Hi

How is this jitter measured ?

Is the link otherwise idle, or do you have a particular qdisc setup to
make sure packets from other flow wont have an effect ?