On Thu, 21 Jan 2016 15:39:26 +0200 "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote: > Hi all! > I have been experimenting with alternative virtio ring layouts, > in order to speed up single stream performance. > > I have just posted a benchmark I wrote for the purpose, and a (partial) > alternative layout implementation. This achieves 20-40% reduction in > virtio overhead in the (default) polling mode. > > http://article.gmane.org/gmane.linux.kernel.virtualization/26889 > > The layout is trying to be as simple as possible, to reduce > the number of cache lines bouncing between CPUs. Some kind of diagram or textual description would really help to review this. > > For benchmarking, the idea is to emulate virtio in user-space, > artificially adding overhead for e.g. signalling to match what happens > in case of a VM. Hm... is this overhead comparable enough between different platform so that you can get a halfway realistic scenario? What about things like endianness conversions? > > I'd be very curious to get feedback on this, in particular, some people > discussed using vectored operations to format virtio ring - would it > conflict with this work? > > You are all welcome to post enhancements or more layout alternatives as > patches. Let me see if I can find time to experiment a bit. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
