B
Bill Blanton
Flightless Bird
On 2/12/2010 14:07, GreyCloud wrote:
> R. C. White wrote:
>> Hi, Gene.
>>
>>> If this will help to think about it: consider a multiboot system in
>>> which
>>> each OS is on its own partition. Clearly, in this case, only one
>>> partition
>>> could be the boot partition - the one with the boot menu - but each
>>> other
>>> OS will ultimately boot from its own partition.
>>
>> Be careful how you use the term "boot partition"!
>>
>>> could be the boot partition - the one with the boot menu
>>
>> But the partition with the boot menu is NOT the Boot Volume. It is the
>> System Partition.
>>
>> And the "boot partition" is more properly called the "boot volume",
>> because it need not be a partition at all. It can be a logical drive
>> in an extended partition. But the System Partition, although sometimes
>> referred to as the "system volume", must be a primary partition.
>>
>>> but each other
>>> OS will ultimately boot from its own partition.
>>
>> No. Each will boot INTO its own boot volume. But each will START in
>> the System Partition - which will present the boot menu - after which
>> the boot process will branch to the chosen boot volume. A
>> multi-booting computer has multiple Boot Volumes, but only a single
>> System Partition.
>>
>> Like a tree with one or more branches. No matter which branch will
>> eventually receive the water from the soil, the water's path up to the
>> branches must start in the trunk of the tree. It can't just jump from
>> the soil to the branch. And no matter which OS's Boot Volume will get
>> chosen, the choice is made by the few files in the System Partition.
>
> Hmmm... reminds me of the old VMS file system. It pretty much allowed
> one to boot into a maximum of 15 different operating systems. It had the
> master directory name of [000000] and then the underlying os was
> [000000].vms or it could be [000000].unix or something else.
> I'm curious as to how win7 structures their os on the hard drive or
> other drives in this fashion.
The on disk structures are basically the same as they have been since
DOS. What changed significantly is the method that the NT loader uses to
find and load the structures (or objects as they are now known).
http://www.microsoft.com/whdc/system/platform/firmware/bcd.mspx
> I also wonder if David Cutler is still
> working at microsoft. If he is, then dave is using his past experience
> with vms. He used to be the team leader for DEC in the old days of VMS.
According to wikipedia he is still there working on Azure.
> R. C. White wrote:
>> Hi, Gene.
>>
>>> If this will help to think about it: consider a multiboot system in
>>> which
>>> each OS is on its own partition. Clearly, in this case, only one
>>> partition
>>> could be the boot partition - the one with the boot menu - but each
>>> other
>>> OS will ultimately boot from its own partition.
>>
>> Be careful how you use the term "boot partition"!
>>
>>> could be the boot partition - the one with the boot menu
>>
>> But the partition with the boot menu is NOT the Boot Volume. It is the
>> System Partition.
>>
>> And the "boot partition" is more properly called the "boot volume",
>> because it need not be a partition at all. It can be a logical drive
>> in an extended partition. But the System Partition, although sometimes
>> referred to as the "system volume", must be a primary partition.
>>
>>> but each other
>>> OS will ultimately boot from its own partition.
>>
>> No. Each will boot INTO its own boot volume. But each will START in
>> the System Partition - which will present the boot menu - after which
>> the boot process will branch to the chosen boot volume. A
>> multi-booting computer has multiple Boot Volumes, but only a single
>> System Partition.
>>
>> Like a tree with one or more branches. No matter which branch will
>> eventually receive the water from the soil, the water's path up to the
>> branches must start in the trunk of the tree. It can't just jump from
>> the soil to the branch. And no matter which OS's Boot Volume will get
>> chosen, the choice is made by the few files in the System Partition.
>
> Hmmm... reminds me of the old VMS file system. It pretty much allowed
> one to boot into a maximum of 15 different operating systems. It had the
> master directory name of [000000] and then the underlying os was
> [000000].vms or it could be [000000].unix or something else.
> I'm curious as to how win7 structures their os on the hard drive or
> other drives in this fashion.
The on disk structures are basically the same as they have been since
DOS. What changed significantly is the method that the NT loader uses to
find and load the structures (or objects as they are now known).
http://www.microsoft.com/whdc/system/platform/firmware/bcd.mspx
> I also wonder if David Cutler is still
> working at microsoft. If he is, then dave is using his past experience
> with vms. He used to be the team leader for DEC in the old days of VMS.
According to wikipedia he is still there working on Azure.