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General Software Discussion / Re: JkDefrag further developed as MyDefrag
« Last post by CWuestefeld on April 30, 2009, 03:45 PM »No defragger can actually specify physical placement of the files on the platter. ...from-bugis (April 07, 2009, 10:40 AM)
Paragon Total Defrag 2009 For Free - Powerful but controversial
dont know who to believe myself ...-tomos (April 30, 2009, 03:04 AM)
I didn't read the referenced article, but the statement is certainly true for any post-DOS computer. Since the advent of IDE drives (remember that stands for "In-Drive Electronics"), not even the OS has control of the actual physical placement. The OS communicates with the hard drive in terms of logical sectors, and the HD maps those logical sectors into physical ones.
This scheme makes it so the OS doesn't need to worry about heads and platters, as we used to have to do with MFM and RLL drives.
It also allows each harddrive to maintain its own list of known bad sectors, which it maps to alternate sectors at the end of the drive. Thus, even a drive that appears perfectly de-fragmented at the logical level may have, unknown to you, physical fragmentation because of mapped-out bad sectors.