Routing benchmarks

[Jacques Fourie]

On Tue, Sep 9, 2008 at 4:40 PM, M. Warner Losh <imp at bsdimp.com> wrote:
> In message: <20080909135021.GR1147 at cicely7.cicely.de>
>            Bernd Walter <ticso at cicely7.cicely.de> writes:
> : On Tue, Sep 09, 2008 at 03:33:30PM +0200, Jacques Fourie wrote:
> : > Hi,
> : >
> : > I've performed some benchmark tests on my Gumstix Connex 400 (Intel
> : > Xscale PXA 255 CPU clocked at 400MHz) with a netDuo expansion board.
> : > This board has two smc network interfaces. I configure the gumstix as
> : > a router and measure network throughput with netperf running on
> : > seperate boxes on either side of the gumstix. My initial tests showed
> : > a TCP throughput of 2Mbit/s. After adapting the smc driver to use DMA
> : > this figure went up to 7Mbit/s. Although this is a significant
> : > improvement, it still seems to be a bit slow. Does anyone have any
> : > tips on how I can go about to try and figure out where the bottleneck
> : > lies?  Initial profiling showed that a significant amount of time was
> : > spent doing memory to memory copies of data, but after the DMA change
> : > profiling does not show any obvious culprits.
> :
> : I don't know the PXA255, but I do know the AT91RM9200 and I expect the
> : PXA255 to be a bit faster.
> : With the RM9200 I can get ~8Mbit/s routing PPPoE with NAT and small
> : ipfw table.
> : This is done with the internal MAC using VLAN, so there is also VLAN
> : overhead.
> : Plain routing should be faster.
>
> Does the gumstick have 100BaseTX?  The AT91RM9200 is 10BaseT only...
> Well, 10Mbps only since the phy is external..
>
> Warner
>
Yes, it does have 100BaseTX - both according to the specs and ifconfig :

smc0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST>
metric 0 mtu 1500
        ether 00:0a:95:a5:47:3a
        media: Ethernet autoselect (100baseTX <full-duplex>)
        status: active
smc1: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST>
metric 0 mtu 1500
        ether 00:0a:95:a5:47:3b
        media: Ethernet autoselect (100baseTX <full-duplex>)
        status: active