Mark Kent wrote:
> Linonut <linonut@xxxxxxxxxxxxx> espoused:
>> * Tim Smith peremptorily fired off this memo:
>>
>>> In article <NEJmk.5818$rD2.1387@xxxxxxxxxxxxxxxxxxxxxx>,
>>> Linonut <linonut@xxxxxxxxxxxxx> wrote:
>>>>
>>>> > http://www.illuminata.com/perspectives/?p=347
>>>
>>> Basically, it uses Linux as a sort of super-GRUB to set up the hardware,
>>> and load the ESX kernel, then the ESX kernel takes over. Then,
>>> cleverly, to get a virtual machine running Linux, to use as a management
>>> console, it uses that Linux to initialize a virtual machine.
>>>
>>> This is a very sensible approach. You are going to use Linux in a VM as
>>> a management console, so you are going to have a full Linux on the disk
>>> anyway. That Linux contains code to detect and initialize hardware.
>>> So, instead of duplicating all that functionality in your kernel, let
>>> Linux boot the hardware and set it up, then your kernel steps in and
>>> pushes Linux aside.
>>>
>>> IBM did a similar thing in OS/2. After the BIOS loaded OS/2 and started
>>> it, OS/2 would create a V86 task, and initialize that with the BIOS and
>>> its state. Then, if you had hardware that OS/2 did not know about but
>>> that the BIOS did, OS/2 would use that virtual BIOS to access that
>>> hardware.
>>>
>>> Come to think of it, Windows 95 did a similar thing with DOS. DOS would
>>> initialize the hardware, load Windows 95, then Windows 95 would
>>> virtualize that DOS.
>>
>> Thanks for that summary and history, Tim.
>>
>
> Windows 95 would virtualise the DOS? I don't think so.
It did. Tim is right about that
>> (Cue some jerk to call me a brown-noser for actually being nice to
>> someone.)
>
> I think his final claim is just wrong. A "thunk" layer springs to mind,
> although I forget the details.
>
A thunking layer is something different
--
Any idiot can run XP. And usually does.
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