So we've recently put a bit of code in our e1000 driver to decrease the qlen based on the speed of the link.
On the surface it seems like a great idea. A driver knows when the link speed changed, and having a 1000 packet deep queue (the default for most kernels now) on top of a 100Mb/s link (or 10Mb/s worst case for us) makes for a *lot* of latency if many packets are queued up in the qdisc. Problem we've seen is that setting this shorter queue causes a large spike in cpu when transmitting using UDP: 100Mb/s link txqueuelen: 1000 Throughput: 92.44 CPU: 5.00 txqueuelen: 100 Throughput: 93.80 CPU: 61.59 Is this expected? any comments? Jesse - 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
