vkernel & GSoC, some questions

Antony Mawer fbsd-hackers at mawer.org
Tue Mar 18 22:32:37 UTC 2008

Jordan Gordeev wrote:
> Matthew Dillon wrote:
>>    We use vkernel's for development and debugging. 
>>    ...
>>    One interesting side-effect of having a vkernel so easily accessible
>>    is that it opens up kernel development to normal programmers.  More
>>    DragonFly developers have been dipping their fingers into the kernel
>>    code in the last 6 months then in all the time before then.  That 
>> alone
>>    justifies the time spent doing it.  Except for hardware device driver
>>    development, the agonizing engineering cycle for kernel development
>>    is completely gone now.
> I have thought of the vkernel primarily as an aid to kernel development 
> (where performance is not a prime concern), not as a virtualisation 
> solution that will compete with Xen and VMWare. It's difficult to 
> compete with thousands of men-hours paid by corporate funding.
> So far nobody has expressed interest in vkernels as a tool for kernel 
> development. And I got the general impression that I've proposed 
> something stupid and useless.

I can see this would be advantageous for lowering the barrier for kernel 
development. The easier this is made, the better chance we have of 
people having a go at fixing issues in some of the unmaintained bits and 
pieces out there.

I recall trying to take the leap into kernel development some years back 
to fix some issues in NWFS and SMBFS; even though I was using VMware for 
testing, I still found the whole compile/install/reboot test cycle a bit 
tedious. If it were a matter of just Ctrl-C'ing a kernel and then 
waiting 5 seconds or a new one to boot up, while still having the rest 
of the machine available "outside" to view/edit source at the same time, 
it would be much simpler...

-- Antony

More information about the freebsd-hackers mailing list