On 04/07/16 20:24, Jordan Justen wrote: > On 2016-04-07 08:07:35, Laszlo Ersek wrote: >> I like the diffstat on this one. >> > > :) > > Series Reviewed-by: Jordan Justen <[email protected]>
Thanks. Committed as aa47e5297851..4a392a451d4d. > Ray, > > I noticed one possible issue. With the new driver, did we lose this > commit? > > commit 1fd376d979221e9765dbec215916f5a6ab92879f > > PcAtChipsetPkg/PciHostBridgeDxe: Improve KVM FIFO I/O read/write > performance I think so. Apologies for not noticing it. :( I hope that Ray can resurrect / reapply the C code directly from the commit you reference above, and the assembly (in NASM syntax) from 6026bf460037 and ace1d0517b65. > Laszlo, > > Someone was reporting slowness with the Windows 7 ISO on irc a few > days back. Maybe this is the cause? > > I don't think this would impact virtio performance. I think you are referring to the following discussion on April 4th: > <Naruni> hello, im having performance issues when using ovmf > (OVMF_CODE-pure-efi.fd from gerd hoffman repo) in QEMU > emulator version 2.3.0 (Debian 1:2.3+dfsg-5ubuntu9.2) > > <Naruni> the specific issue im having is slow performance while trying > to install win7, the initial screen 'loading windows files' > is very slow and im only getting about 1 MB/sec disk IO > according to iotop > > <Naruni> if i use a VM in bios mode it operates at full performance > > <Naruni> this behavior is the same across multiple distros (ubuntu, > debian, arch, and gentoo) > > <Naruni> kvm is enabled and working according to qemu monitor > > <lersek> Naruni, what kind of virtual disk are you using? Are you > using virtio-blk or virtio-scsi with OVMF as well? > > <lersek> Naruni, also, I guess the best "advice" I can give at the > moment is: "just use the most recent upstream QEMU release". Unfortunately, "Naruni" didn't respond (I'll admit that I noticed his question only 90 minutes later or so). However, I am now putting this together with an email, on the vfio-users list (also April 4th): https://www.redhat.com/archives/vfio-users/2016-April/msg00029.html The description is practically identical, so I'm thinking the same user reported it. I'm adding the email address from the latter message to the Cc list now. Mark, are you Naruni? :) Unfortunately, the report doesn't name the version of Gerd's OVMF RPM in use. It also doesn't say whether the CPU was pegged while experiencing the slow performance. The "multiple distros" comment in the IRC report is not clear -- does that mean multiple distros as guests, or hosts? I guess it's the former; first, the host is reported as "QEMU emulator version 2.3.0 (Debian 1:2.3+dfsg-5ubuntu9.2)", while the domain XML pasted into Mark's email lists an ArchLinux installer ISO (i.e., guest). The domain XML clarifies another thing: the CD-ROM is IDE, not virtio-scsi. Also, there is no other disk drive (of any kind). Let me see if I can reproduce this, and perhaps bisect it. Mark, if you want to follow up on this list (= edk2-devel), please note that first you will have to subscribe to the list (and await the confirmation), at <https://lists.01.org/mailman/listinfo/edk2-devel>. Thanks Laszlo _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
