mysterious discrepancy in the reported free space on two identicalusb drives
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From: Jonathan de Boyne Pollard on 18 Feb 2010 15:17 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body bgcolor="#ffffff" text="#000000"> <blockquote cite="mid:70c04a46-ca9e-4c51-9766-a0a5998c4ba0(a)z11g2000yqz.googlegroups.com" type="cite"> <blockquote type="cite"> <blockquote type="cite"> <p wrap=""><a href="http://img237.imageshack.us/img237/2852/passportdiscrepancy.jpg">http://img237.imageshack.us/img237/2852/passportdiscrepancy.jpg</a><br> I have two identical WD 1tb passport usb drives filled with identical data. [...]<br> </p> </blockquote> <p>... but not necessarily identical metadata. That 28KiB difference is a mere 28 deleted MFT records, for example. Or it could be journal entries, security descriptor records, or quite a number of other things.</p> </blockquote> <p>But isn't this the kind of meta data that is supposed to disappear when the recyclebin is emptied?</p> </blockquote> <p>Put simply: No. Deleted MFT records are nothing to do with files in the recycle bin, for example.</p> <blockquote cite="mid:70c04a46-ca9e-4c51-9766-a0a5998c4ba0(a)z11g2000yqz.googlegroups.com" type="cite"> <p>Is there any other way to clear any superfluous data somehow?</p> </blockquote> <p>Put simply: Short of drastic measures such as reformatting the volume, no. The MFT doesn't shrink in normal operation, for example. And the security descriptor stream is only compacted by <code>chkdsk</code>. (See MSKB 919241.)</p> <blockquote cite="mid:70c04a46-ca9e-4c51-9766-a0a5998c4ba0(a)z11g2000yqz.googlegroups.com" type="cite"> <p>we're talking about two identical drives and identical data that is supposed to be stored on the drive.</p> </blockquote> <p>No, we're not. As I said, the metadata are not necessarily identical.</p> </body> </html> |