On Thu, Jun 26, 2014 at 4:58 AM, Paolo Bonzini <pbonz...@redhat.com> wrote: > Il 25/06/2014 19:53, Etienne Martineau ha scritto: > >> >> It seems to me that there is a scale issue O(n) in >> memory_region_transaction_commit(). >> >> Basically the time it takes to rebuild the memory view during device >> assignment >> pci_bridge_update_mappings() increase linearly with respect to the number >> of >> device already assigned to the guest. > > > That's correct, unfortunately. It can be fixed, it's not hard but also not > trivial. > > Basically you can detect address spaces whose memory region is an alias of > an address space's root memory region. You can then reuse that address > space's FlatView instead of building another one. >
Sounds like my shareable address spaces scheme: http://lists.gnu.org/archive/html/qemu-devel/2014-06/msg00366.html Its not MR alias aware but shouldn't be too hard to extend. Would this help? Regards, Peter > Paolo >
