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is linux more windows friendly or more mac friendly?

Started by cooldude!, March 22, 2010, 11:50:34 AM

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Mad Penguin

Ok, here we go;

QuoteMac does NOT use the FreeBSD kerne

I'm not sure that's entirely accurate ... if we've any Mac XNU kernel guru's knocking around, correct me if I'm wrong, but as I understand it the concept of a microkernel is much like that of a virtualization hypervisor. Essentially the microkernel does all the basic system resource allocation, but the actual useful stuff all happens inside a virtual environment provided by the microkernel. In much the same way as with a hypervisor, if the 'actual' OS crashes inside it's VM, the microkernel lives on and indeed has the option of restarted the failed OS without restarting 'everything'. (very useful in the context of a hypervisor running a number of VM's / operating systems)

Obviously Mac's don't run lots of Operating Systems, just the one, but again, as I understand it the microkernel starts up a number of "VM's" (for lack of better terminology) and allocates them to different tasks, so for example device drivers run in a virtual environment and if a device driver crashes (something that would be likely to crash a Linux box) the microkernel can simply reload/restart it.

But I think what I'm coming to, is that on a Mac, one of these microkernel VM's actually runs a modified version of BSD, which is what does all the 'real' work (i.e. what you see) .. so .. whereas it's fair to say that a Mac does not run on FreeBSD (because it runs the XNU microkernel) , I also think it's fair to say that it does use the FreeBSD kernel, albeit a modified version.

Effectively I think you could say that Mac OS/X is a microkernel'd version of FreeBSD, maybe we could say FreeBSD NG (?!)
https://twitter.com/garethbult
https://gareth.bult.co.uk


BkS

Quote from: Mad Penguin on June 18, 2010, 09:56:06 PM
Ok, here we go;

QuoteMac does NOT use the FreeBSD kerne

I'm not sure that's entirely accurate ... if we've any Mac XNU kernel guru's knocking around, correct me if I'm wrong, but as I understand it the concept of a microkernel is much like that of a virtualization hypervisor. Essentially the microkernel does all the basic system resource allocation, but the actual useful stuff all happens inside a virtual environment provided by the microkernel. In much the same way as with a hypervisor, if the 'actual' OS crashes inside it's VM, the microkernel lives on and indeed has the option of restarted the failed OS without restarting 'everything'. (very useful in the context of a hypervisor running a number of VM's / operating systems)

Obviously Mac's don't run lots of Operating Systems, just the one, but again, as I understand it the microkernel starts up a number of "VM's" (for lack of better terminology) and allocates them to different tasks, so for example device drivers run in a virtual environment and if a device driver crashes (something that would be likely to crash a Linux box) the microkernel can simply reload/restart it.

But I think what I'm coming to, is that on a Mac, one of these microkernel VM's actually runs a modified version of BSD, which is what does all the 'real' work (i.e. what you see) .. so .. whereas it's fair to say that a Mac does not run on FreeBSD (because it runs the XNU microkernel) , I also think it's fair to say that it does use the FreeBSD kernel, albeit a modified version.

Effectively I think you could say that Mac OS/X is a microkernel'd version of FreeBSD, maybe we could say FreeBSD NG (?!)


how do you know all this stuff  ??? :-\?
If you try to look through Windows, you can see what the person is doing.
If you try to look through a Penguin, it WILL bite you.

Mad Penguin

https://twitter.com/garethbult
https://gareth.bult.co.uk

BkS

If you try to look through Windows, you can see what the person is doing.
If you try to look through a Penguin, it WILL bite you.