On Thu, 2009-01-29 at 12:23 +0100, Tore Anderson wrote: > * Thomas Jacob > > > Some newer NICs (some of Intel's for instance) support several packet > > queues to make it possible to deal with just this problem. > > > > Check out http://lwn.net/Articles/289137/ for a start... > > Interesting link, thanks! However, I was under the impression that the > problem is incoming (RX) frames, that causes an interrupt to be raised > on a certain CPU (core) which in turn causes the frame to be processed > by that particular CPU by the NET_RX softirq handler. Correct... maybe this info isn't quite up to date... > The multiqueue patch seem to be about being able to submit outgoing (TX) > frames to multiple hardware queues. So I don't think it will make much > of a difference for me? Don't know about the current state of general Linux driver support for this, but the Intel hardware also supports multiple RX queues: http://www.intel.com/network/connectivity/resources/technologies/10_gigabit_ethernet.htm and their current ixgbe driver docs say: RSS - Receive Side Scaling (or multiple queues for receives) ------------------------------------------------------------ Valid Range: 0 - 16 0 = disables RSS 1 = enables RSS and sets the descriptor queue count to 16 or the number of online cpus, whichever is less. 2-16 = enables RSS, with 2-16 queues Default Value: 1 RSS also effects the number of transmit queues allocated on 2.6.23 and newer kernels with CONFIG_NETDEVICES_MULTIQUEUE set in the kernel .config file. CONFIG_NETDEVICES_MULTIQUEUE only exists from 2.6.23 to 2.6.26. Other options enable multiqueue in 2.6.27 and newer kernels. MQ - Multi Queue ---------------- Valid Range: 0, 1 0 = Disables Multiple Queue support 1 = Enabled Multiple Queue support (a prerequisite for RSS) Default Value: 1 -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
