[SeaBIOS] Reducing SeaBIOS kernel entry time

[Stefan Hajnoczi]

On Fri, Jul 3, 2015 at 2:13 PM, Kevin O'Connor <kevin at koconnor.net> wrote:
> On Fri, Jul 03, 2015 at 10:33:56AM +0100, Stefan Hajnoczi wrote:
>> Hi,
>> qboot (https://github.com/bonzini/qboot) is a stripped down firmware
>> providing only what is needed to boot a Linux kernel on x86.  I wonder
>> if there is room to achieve similar results with SeaBIOS for the
>> lightweight virtual machine use case.
>>
>> The goal is to enter the kernel within 20 milliseconds.  (That's the
>> number I measured with qboot.)
>>
>> Kevin: Have you looked at SeaBIOS startup time and do you think this
>> use case is within the scope of what SeaBIOS is intended for?
>>
>> Marc is beginning to profile boot times and any pointers would be helpful.
>
> Hi Stefan,
>
> I took a look a month or so ago:
>
> http://article.gmane.org/gmane.comp.emulators.kvm.devel/136207
>
> Last test I ran I had SeaBIOS down to 16ms (not including the time to
> deploy or jump to the linux kernel).  More reductions are also
> possible - the above was just with Kconfig settings.
>
> Let me know if you want more info on how I did that.

That sounds interesting.  Do you have a .config or git branch?

Stefan