freebsd stable - Jul 2006 - How to setup polling on 'bge' interface

Hi,

I'm trying to setup polling in my box. I'm using these options:

	options DEVICE_POLLING
	options HZ=1000

and in the rc.conf:

ifconfig_bge0="inet xxx.xxx.xxx.xxx/xx polling media 1000baseTX
mediaopt full-duplex"

But I always get some packet loss. 

I'm using FreeBSD 6.1 and SMP option in the kernel. I saw something
about polling and SMP [1] but I ran 'config' and 'make' without
any
problem. 

Am I forgetting something else? 

[1] http://info.iet.unipi.it/~luigi/polling/


-- 
Att.,

Marcelo Gardini
Registro .br

On Tue, Jul 11, 2006 at 04:09:08PM -0300, Marcelo Gardini do Amaral wrote:
> Hi,
> 
> I'm trying to setup polling in my box. [...]
> But I always get some packet loss. 
A few points:

- Polling and SMP are compatible in 6.1.  In fact, they were compatible
  in earlier versions too; basically it's just the compile-time check
  that had to be "fixed."

- You may have to adjust some parameters in the kern.polling sysctl
  tree - specifically, kern.polling.burst_max, kern.polling.each_burst
  and kern.polling.user_frac might need tweaking.

- The polling feedback algorithm does not work very well if your
  workload is focused largely on per-packet tasks (such as routing or
  bridging).  You'll find that there is still idle CPU time at the
  point you start dropping packets.  I have some work in progress to
  address this, but it's not yet committed.

- Polling's major advantage is the avoidance of livelock on UP systems,
  and not improved performance.

What level of traffic are you putting through this box?  Is it routing/
bridging, or an endpoint like a web server?

Ed Maste