On Wed, Feb 22, 2006 at 10:56:31AM -0800, Ben Greear wrote: > For VLANs, make sure that the 'multi-skb' is always zero. This is because > the VLAN code modifies the skb by re-assigning the skb->dev to the > underlying > device. > > I'm not sure if this is the problem you hit, but it could be...
Yup, that was it. Of course, now it doesn't send as fast. Hrmph. :) On this older Xeon 2.4 Ghz w/533 FSB and e1000 & tg3 @ PCI-X 133 Mhz 64 bit, SMP kernel, single pktgen thread, I'm only seeing: clone_skb=0, 802.1Q tagging, 60 byte: e1000: 558526pps 268Mb/sec (268092480bps) errors: 0 tg3: 621260pps 298Mb/sec (298204800bps) errors: 0 clone_skb=0, no 802.1Q, 60 byte: e1000: 664558pps 318Mb/sec (318987840bps) errors: 0 tg3: 772650pps 370Mb/sec (370872000bps) errors: 0 clone_skb=16384, no 802.1Q, 60 byte: e1000: 684206pps 328Mb/sec (328418880bps) errors: 0 tg3: 1069830pps 513Mb/sec (513518400bps) errors: 0 I tried on an Opteron 140 box and it was faster for both cards, but not by much. oprofile showed a lot of do_getttimeofday, so I hacked a bunch of calls out of pktgen -- I noticed the CPU time shifted around but the throughput was still the same as before, as if it's card or bus limited. Why is it so difficult to actually get 1 Gbps of small packets? I also tried changing ring buffer sizes, txqueuelen, interrupt coalescing settings, etc... all I was able to do was make it slower or very slightly faster. Simon- - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
