Linux kernel compatability

David Xu davidxu at freebsd.org
Wed Jan 5 01:39:32 UTC 2011


Scott Long wrote:
> On Jan 4, 2011, at 1:14 AM, Poul-Henning Kamp wrote:
>> In message <alpine.BSF.2.00.1101031333400.1450 at desktop>, Jeff Roberson writes:
>>
>>> Also, linux likes to change things very rapidly.  Not to mention a lot of 
>>> their APIs go against the grain on BSD and we would not find them 
>>> aesthetically or architecturally pleasing.
>> Absolutely.
>>
>> But we, as a project, must also weigh the cost of our sensibilities
>> and preferences, against how much work we must expend to uphold them.
>>
> 
> I have mixed feelings about Jeff's shim layer.  On the plus side, I think that there's value to emulation without copying.  On the negative side, I agree with ALexander's concern that it's a large chuck of code to be maintained.  Emulation isn't a bad thing.  It allows IHV's as well as individual developers to take baby steps with getting familiar with FreeBSD.    It lowers the barrier to entry.  The ones who aren't going to put in the effort to making the leap from "emulation" to "native" likely aren't going to take the leap with going from "nothing" to "native" either.  I understand the argument that it will coddle people into using just the emulation and not the native interfaces, thus degrading the value of the native interfaces.  I'm just not sure how much I believe that in my experience.
> 
> I recall years ago Matt Jacob mentioning with some concern that the project seemed to be aimed at creating a "FreeSolaris" of sorts; many of the architectural decisions seemed to be based on the argument that Solaris was doing it, so FreeBSD should too.  That's fine, and there's a certain amount of comfort in following an arguably decent architectural standard like Solaris, though I understand what I believed to be Matt's point about retaining some identity and exploring new paths rather than just following old paths.
> 
> In my not so humble opinion, Linux is not an architectural model to be envied or copied, regardless of how pragmatic it might seem.  Sure, gratuitous differences can be argued against, but there are a lot of fundamental architectural things that linux succeed at purely by brute force of will, and nothing more.  FreeBSD should be careful to not envy that model.  I think that there's a lot less value in both the long and short terms in a "FreeLinux" than in a "FreeSolaris", and neither are all that good in the long term.
> 
> Having an emulation gives people a lower barrier to entry and some stepping stones to getting comfortable with FreeBSD.  It gives them a series of achievable goals with costs and benefits at each step that can be weighed.  Aiming at simply evolving the native interfaces to be like linux simply means that FreeBSD becomes a poor copy of linux with nothing else under the surface to set it apart or create an attraction.
> 
> Scott
> 

Which OS can attract me ? Linux and FreeSolarisBSD all are old 
technology, I also have mixed feeling, I think I can not learn more
from these OSes. :-)

Regards,
David Xu




More information about the freebsd-arch mailing list