From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Regression on TX throughput when using bonding
Date: Thu, 14 Jun 2012 16:29:17 +0200
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To: Jean-Michel Hautbois <jhautbois@gmail.com>
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On Thu, 2012-06-14 at 16:14 +0200, Jean-Michel Hautbois wrote:

> ~# tc -s -d qdisc show dev eth1 > before_tc && sleep 10 && tc -s -d
> qdisc show dev eth1 > after_tc && ./beforeafter before_tc after_tc
> qdisc mq 0: root
>  Sent 3185900568 bytes 788681 pkt (dropped 0, overlimits 0 requeues 620)
>  backlog 0b 0p requeues 620
> 
> As you can see, 2.5Gbps without any difficulties :).
> 
> Thanks,
> JM

I have no idea why throughput on ethernet link is changed.

There is another bug elsewhere.  Use a thousand of sockets instead of
few, and you'll hit the bug.

Orphaning skbs should not lower speed of the device, only drops excess
packets, instead of blocking the application, waiting the socket wmem
alloc being freed by destructors.

Are you playing with process priorities ?

If the ksoftirqd cannot run, this could explain the problem.