File size??

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I have 3tb in exfat. I know why you ask but it works on both mac and pc. But its super unreliable and stopped working. Still works on pc but not mac. Repair does nothing. So I cloned the disk I forget what program in windows 8.1 to another internal. Then erased the external as mac (so its fresh now and recognizes) and then put both into mac. I have the dual sata dock for the internals. I then cloned the disk with carbon copy cloner.

I know its mac only now but at least it reads and I can always grab later form a flash stick or something and transfer to PC if I need any files. But exfat was too unreliable and stopped working finally.

Anyhow I double checked the files and folders. All are the same size. But it says 900 something gb available and 2tb used on my exfat.

But my mac os x journaled says only 1.5tb used and 1.5tb free approximately.

How can it be if both files are the same size that I have 1.5tb free on mac and less than 1tb on exfat.

Is this a difference between the file systems. Both are the same size but one says 2tb used and one only 1.5tb used.

How can this be?
 

bobtomay

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Best I can tell...
512 byte sectors (or cluster size) with HFS+
128KB with ExFAT on a 3TB drive size

A cluster can only hold a single file (or part of a file)
a 1 byte file takes up an entire cluster.
The smaller the cluster size, the less wasted space on a drive.

(128KB = 128,000 bytes)
 

chscag

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"bobtomay" is correct. The terminology is called "cluster slack". The larger the drive, the larger the cluster size and greater the slack becomes. The FAT file system is very wasteful especially as you apply it to large partitions or drives. HFS and NTFS both use small cluster sizes regardless of drive size. Also, FAT is a non journaling file system and highly prone to errors. Both HFS and NTFS are journaled file systems.
 
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Great answers thanks. I asked on apple forums and mac rumors and no replys. Sound good. So I'll go ahead and erase the exfat and just keep the external. Thanks.
 
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??? My lingo translator is not working! ;)
 

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