Anthony Liguori wrote: >> How about the other way round: when the vlan consumer detects it can >> no longer receive packets, it tells that to the vlan. When all vlan >> consumers can no longer receive, tell the producer to stop >> producing. For the tap producer, this is simply removing its fd from >> the read poll list. When a vlan consumer becomes ready to receive >> again, it tells the vlan, which tells the producers, which then >> install their fds back again. > > Yeah, that's a nice idea. I'll think about it. I don't know if it's > really worth doing as an intermediate step though. What I'd really > like to do is have a vlan interface where consumers published all of > their receive buffers. Then there's no need for notifications of > receive-ability.
That's definitely better, and is also more multiqueue nic / vringfd friendly. I still think interrupt-on-halfway-mark is needed much more urgently. It deals with concurrency much better: rx: host interrupts guest on halfway mark guest starts processing packets host keeps delivering tx: guest kicks host on halfway mark host starts processing packets second vcpu on guest keeps on queueing It's also much better with multiqueue NICs, where there's no socket buffer to hold the packets while we're out of descriptors. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic. ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
