On Tue, Jul 01, 2008 at 11:05:03AM +0800, Sepherosa Ziehau wrote: > On 7/1/08, Paul <[EMAIL PROTECTED]> wrote: > > All the NIC drivers in 7 pretty much use interrupt moderation so it can > > I am not quite sure whether em(4)'s RX interrupt moderation works as > expected or not. But, AFAIK, nfe(4) and re(4) does not have RX > interrupt moderation. Their TX interrupt moderation could be mimiced > by using their hardware timer and disabling their TX interrupt. > > The lacking of RX im is difficult to handle, I could imagine following way: > - During init, enable RX intr > - When RX intr comes, disable RX intr and set up hardware timer intr > - When timer intr comes and no RX happens, disable timer intr and enable RX > intr >
I guess adaptive polling would give the same effect withtout sacrificing CPU cycles. > Properly configured #RX desc and timer intr interval will be required > to make sure that the RX desc collection could keep up with the > hardware speed. I used pure timer intr (8000Hz) on nfe(4) in dfly w/ > good result, i.e. TX/RX @linespeed without livelocking the system. I thought that too for a while but I prefer to hardware intertrrupt moderation feature. Of course I still have no clue how to enable that interrupt feature on nvidia controllers. :-( > The drawback of pure timer intr is that you waste extra cpu power, > when there is nothing to process. > > > never lock the machine anyway.. This effectively kills polling and it > > really > > no longer has any use except to be able to have a fraction of the cpu set > > Oh? Really? :] > > Best Regards, > sephe > > -- > Live Free or Die -- Regards, Pyun YongHyeon _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "[EMAIL PROTECTED]"