From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jaswinder Singh Rajput <jaswinder@kernel.org>
Subject: Re: When does Linux drop UDP packets?
Date: Thu, 04 Jun 2009 23:16:16 +0530
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Cc: Philipp Reh <sefi@s-e-f-i.de>, LKML <linux-kernel@vger.kernel.org>,
	netdev <netdev@vger.kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
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On Thu, 2009-06-04 at 12:34 -0400, Steven Rostedt wrote:

> BTW, I used ftrace to look into this:
> 
> Enable:
> 
> 	CONFIG_FTRACE
> 	CONFIG_FUNCTION_TRACER
> 	CONFIG_FUNCITON_GRAPH_TRACER
> 	CONFIG_DYNAMIC_FTRACE
> 
> Compile and boot:
> 
> # mount -t debugfs nodev /sys/kernel/debug

Very glad to see you following standards ;-)

> # cd /sys/kernel/debug

hmm you mean # cd /sys/kernel/debug/tracing

> # echo udp_rcv > set_graph_function
> # echo function_graph > current_tracer
> # cat trace
> 

Anyway you can also see UDP packet drops when you increase network and
CPU load.

--
JSR