FreeBSD boxes as a 'router'...

[Barney Cordoba]

--- On Tue, 11/20/12, Ingo Flaschberger <if at xip.at> wrote:

> From: Ingo Flaschberger <if at xip.at>
> Subject: Re: FreeBSD boxes as a 'router'...
> To: freebsd-net at freebsd.org
> Date: Tuesday, November 20, 2012, 6:04 PM
> Am 20.11.2012 23:49, schrieb Alfred
> Perlstein:
> > On 11/20/12 2:42 PM, Jim Thompson wrote:
> >> On Nov 20, 2012, at 3:52 PM, Barney Cordoba <barney_cordoba at yahoo.com>
> wrote:
> >> 
> >> You're entitled to your opinion, but experimental
> results have tended to show yours incorrect.
> >> 
> >> Jim
> > Agree with Jim.  If you want pure packet
> performance you burn a core to run a polling loop. 
> 
> At new systems, without polling I had better performance and
> no live-locks,
> at old systems (Intel 82541GI) polling prevent live-locks.
> 
> Best test:
> Loop a GigE Switch, inject a Packet and plug it into the
> test-box.

Yeah, thats a good real-world test.

To me "performance" is not "burning a cpu" to get some extra pps. 
Performance is not dropping buckets of packets. Performance is using
less cpu to do the same amount of work. 

Is a machine that benchmarks at 998Mb/s at 95% cpu really a "higher
performance" system than one that does 970Mb/s and uses 50% of the cpu?

The measure of performance is to manage an entire load without dropping
any packets. If your machine goes into live-lock, then you need more
machine. Hacking it so that it drops packets is hardly a solution.

BC