Update: >From our testing this bug affects KVM Hypervisors on Intel processors that have the EPT feature enabled with Kernels 3.0 and greater. A list of Intel EPT supported CPUs here (http://ark.intel.com/Products/VirtualizationTechnology).
When using a KVM Hypervisor Host with Linux kernel 3.0 or newer kernel with Intel EPT this bug shows itself. If the kvm_intel module is loaded with option "ept=N" guest performance is significantly decreased versus enabled, but it does maintain consistent performance pre and post restoration/migration. Exceptions: -A KVM Host with 2.6.32 or 2.6.39 Kernel with EPT enabled this bug is not triggered. -A KVM Host without the EPT feature enabled Intel CPU this bug is not triggered. -A KVM Host with Kernel 3.0+ and EPT kvm_intel module option disabled in this bug is not triggered A KVM hypervisor with EPT enabled on Linux Kernel > 3.0 appears to be the key here. -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to qemu-kvm in Ubuntu. https://bugs.launchpad.net/bugs/1100843 Title: Live Migration Causes Performance Issues To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1100843/+subscriptions -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs
