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Old 15th June 2011
Beastie Beastie is offline
Daemonology student
 
Join Date: Jan 2009
Location: /dev/earth0
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Quote:
Originally Posted by sharris View Post
WHERE IS this freaking FIRST 1024 BYTES LOCATED at the head or at the center
Head? You mean the read-write head, eh? o_O

The first X sectors are located in the very first track which is, as you've already said it ("data saving begin at the first OUTER edge of the HDD"), on the periphery of the platter.

Quote:
Originally Posted by sharris View Post
it indicated the MBR to be at the CENTER of the drive
And I presume it's wrong.

Quote:
Originally Posted by sharris View Post
I pop in Partition Commander and I see two allocate free-space at the end of the HDD, WTF. My 1GB plus 7MB out of no-where.
If it's free space, then it's not allocated. If it has an entry with a specific operating system ID, then it's a slice and not free space anymore.
To preserve backward compatibility, partitions (the "BSD slice" ones) are aligned to cylinder boundaries. Most of the time, this wastes hundreds/thousands of sectors, i.e. couple of MB, between slices and at the end of the disk.

Quote:
Originally Posted by sharris View Post
A Few other time there would be 64 or so kilobyte between partition-2 and partition-3 etc, where FreeBSD lives even on my Windows machines
Especially on Windows. Older versions to be precise.

Quote:
Originally Posted by sharris View Post
This indicates to me that the MBR is at the CENTER of the HDD living on top of a fool known as the hard-di*K controller
Seriously? How did you reach that conclusion? It's on the periphery of one of the platters and nowhere else. It's a sector like any other. The only thing special about it is that the BIOS loads it after the POST.

Quote:
Originally Posted by sharris View Post
maybe so for Windows ONLY drives, but this is not true for a partitioned HDD. Each PARTITION has his own INNER and OUTER and it has less distance to travel
All this has nothing to do with Windows or any other operating system or the filesystem that is written on the disk.
Data is written on sectors from the outer tracks to the inner ones. Partitions/BSD slices (as well as logical or BSD partitions) are linear and also start from the outer tracks and move in to the inner ones. The data transfer rate is higher in the outer cylinders compared to the inner ones because they contain more sectors. Period.

Search the Internet for "zone bit recording".
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