Netgraph performance with ng_ipfw

Eugene Perevyazko john at
Thu Mar 4 12:49:05 UTC 2010

On Sat, Jan 23, 2010 at 03:32:11AM +0600, Евгений wrote:
> Hi, 
> I have several routers under heavy load, running FreeBSD 7.2
> These routers use Netgraph to impelement traffic shaping and accouting
> (using ng_car and ng_netflow nodes). 
> The second question is about the effectiveness of Netgraph queueing and ng_ipfw node with SMP kernel...
> one of the ng_queue* processes will take 100% time of one CPU core, when the others will not 
> process anything.
> I have seen such behavior on my routers - at peak load, one of ng_queue* processes takes 100% of one core, 
> and the other processes are seen in top taking 0% of CPU. 
> My question is, can it somehow be fixed?

I see the same behaviour with ng_nat and ng_ipfw.
7-S as of Nov 2009 on Xeon E5410 (4 cores).
16 ng_nat nodes connected to ng_ipfw.
Sometimes one ng_queue eats 100% of one core while other 3 ng_queues sit idle.
I'm going to set queueing on all ng_nat's hooks to see if it will help.

Eugene Perevyazko

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