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Subject: Re: many rx packets dropped since 2.6.37
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Chris <xchris89x@googlemail.com>
Cc: linux-kernel@vger.kernel.org
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Date: Wed, 25 Apr 2012 19:43:01 +0200
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On Wed, 2012-04-25 at 16:38 +0200, Chris wrote:
> 2012/4/25 Eric Dumazet <eric.dumazet@gmail.com>:
> >> Why do we see dropped packets only in virtual environments and bonded
> >> network interfaces and not on real network interfaces?
> >
> > This has to be investigated, eventually.
> 
> Do you have the opportunity to test it? Just install fedora 16 (linux
> 3.3) or ubuntu 12.04 (linux 3.2) as guest under kvm and use as virtual
> network card virtio_net or e1000.
> 
> You will see many lost rx packets and i have no idea why???


You can use drop_monitor / dropwatch to figure out

https://fedorahosted.org/dropwatch/

http://prefetch.net/blog/index.php/2011/07/11/using-netstat-and-dropwatch-to-observe-packet-loss-on-linux-servers/

Or just ignore the thing, if no user side effect is noticed.