On Thu, Jan 11, 2007 at 05:53:56PM -0800, Matthew Dillon wrote: [MMU fault, modification and loading issues] ... > I don't have numbers for page table faults, but at least for those > the real kernel doesn't have to drop into the virtual kernel unless > the emualted page table is missing the page table entry for the VA. > (the real kernel handles setting the VPTE_M bit itself). I still have > some work to do there today and tomorrow that might improve performance > a bit.
VMWare, I believe, actually does a partial binary translation of MMU instructions and higher order operations into direct kernel calls that can modify the host image directly. I guess that helps out with context switching performance, but this is a chronic problem for all Xen-ish systems that I know of that doesn't have a really transparent solution. bill
