Trimming CC list.
On Thu, Aug 06, 2015 at 05:53:26PM +0200, Marc Marí wrote:
On Thu, 6 Aug 2015 11:30:43 -0400 "Kevin O'Connor" kevin@koconnor.net wrote:
On Thu, Aug 06, 2015 at 02:37:45PM +0200, Marc Marí wrote:
On Thu, 6 Aug 2015 13:27:16 +0100 Stefan Hajnoczi stefanha@gmail.com wrote:
On Thu, Aug 6, 2015 at 12:00 PM, Marc Marí markmb@redhat.com wrote:
When running a Linux guest on top of QEMU, using the -kernel options, this is the timing improvement for x86:
QEMU commit 2be4f242b50a8 and SeaBIOS commit 908a58c1d5ff QEMU startup time: .078 BIOS startup time: .060 Kernel setup time: .578 Total time: .716
QEMU with this patch series and SeaBIOS with this patch series QEMU startup time: .080 BIOS startup time: .039 Kernel setup time: .002 Total time: .121
Impressive results!
Is this a fully-featured QEMU build or did you disable things?
Is this the default SeaBIOS build or did you disable things?
This is the default QEMU configuration I get for my system. It's not a fully-featured QEMU, but it has a lot of things enabled. SeaBIOS has a default configuration (with debugging disabled).
Thanks!
What qemu command-line did you use during testing? Also, do you have a quick primer on how to use the kvm trace stuff to obtain timings?
The command line I used is:
x86_64-softmmu/qemu-system-x86_64 --enable-kvm \ -kernel /boot/vmlinuz-4.0.7-300.fc22.x86_64 \ -L pc-bios/optionrom/ \ -bios roms/seabios/out/bios.bin -nographic
Thanks. One thing that immediately pops up is that even though "-nographic" is used, it looks like QEMU still emulates a VGA device and that device has an option rom that takes several milliseconds to init the display hardware. Adding "-device VGA,romfile=" to the qemu command line will further reduce the boot time by avoiding this hardware init delay.
-Kevin