On 15 Nov 2018, at 06:59, A Z <a...@zegelin.com> wrote: > > This is an issue that involves a combination of different software packages, > so my apologies in advance if this is the wrong list to post on. > > I'm experiencing terrible boot times when I assign a large amount of RAM to a > VM when used in combination with VIFO/PCI-passthrough. > > On a VM with a Nvidia GTX 970 + USB controller and 24GiB of RAM assigned, the > time to the TianoCore splash screen is ~5 minutes. It's then ~30 seconds > before Windows 10 begins to boot (spinning dots). During this time, the QEMU > CPU core threads are 100% busy. >
This sounds quite like a problem I used to have in the past with certain versions of OVMF and the Linux kernel. If I remember correctly, some memory ranges would get marked as non-cacheable, which resulted in the terrible slowdown you describe. The resolution back then was to stick to older versions of both the firmware and the kernel. I still keep around an older version of OVMF that I used until recently - edk2.git-ovmf-x64-0-20160714.b1992.gfc3005.noarch.rpm. You could download the RPM here and try if it works for you: https://exa.flopser.de/s/z3cjqFUlZ2gBPCy <https://exa.flopser.de/s/z3cjqFUlZ2gBPCy> Recent QEMU versions started complaining about firmware incompatibilities, so I tried the latest RPM from Kraxel (https://www.kraxel.org/repos/jenkins/edk2/ <https://www.kraxel.org/repos/jenkins/edk2/>) and it works just fine. The host system is Arch Linux with the latest Arch kernel and QEMU. Cheers, Hristo > According to `perf`, the QMU CPU core threads are spending most of their time > waiting on a spinlock over kvm->mmu_lock that's created by kvm_zap_gfn_range. > > I'm fairly certain that ~1 year ago (if not longer) the same configuration > didn't take this long to boot. > > Regards, > Adam > _______________________________________________ > vfio-users mailing list > vfio-users@redhat.com > https://www.redhat.com/mailman/listinfo/vfio-users
_______________________________________________ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
