Subject: Re: [PATCH 1/2]: [NET_SCHED]: Make all rate based scheduler work with TSO.

From: Bill Fink <[email-masked]>
Date: Tue, 4 Sep 2007 13:40:15 -0400

On Tue, 04 Sep 2007, Patrick McHardy wrote:

> Bill Fink wrote:
> > On Sat, 1 Sep 2007, Jesper Dangaard Brouer wrote:
> >
> >>On Sat, 1 Sep 2007, Patrick McHardy wrote:
> >>>
> >>>It still won't work properly with TSO (TBF for example already drops
> >>>oversized packets during ->enqueue), but its a good cleanup anyway.
> >>
> >>Then lets call it a cleanup of the L2T macros.  In the next step we will 
> >>fix the different schedulers, to use the ability to lookup larger sized 
> >>packets. (I did notice the TBF scheduler would drop oversized packets).
> > 
> > Hmmm.  I guess this is also why TBF doesn't seem to work with 9000 byte
> > jumbo frames.
> > 
> > [root@lang4 ~]# tc qdisc add dev eth2 root tbf rate 2gbit buffer 5000000 limit 18000
> 
> Yes, you need to specify the MTU on the command line for
> jumbo frames.

Thanks!  Works much better now, although it does slightly exceed
the specified rate.

[root@lang4 ~]# tc qdisc add dev eth2 root tbf rate 2gbit buffer 5000000 limit 18000 mtu 9000

[root@lang4 ~]# ./nuttcp-5.5.5 -w10m 192.168.88.14
 2465.6729 MB /  10.08 sec = 2051.8241 Mbps 19 %TX 13 %RX

[root@lang4 ~]# ./nuttcp-5.5.5 -M1460 -w10m 192.168.88.14
 2785.5000 MB /  10.00 sec = 2335.6569 Mbps 100 %TX 26 %RX

						-Bill