Path: utzoo!mnetor!uunet!husc6!bbn!rochester!pt.cs.cmu.edu!andrew.cmu.edu!jv0l+ From: jv0l+@andrew.cmu.edu (Justin Chris Vallon) Newsgroups: comp.sys.mac Subject: Re: Physical Storage Amounts on Different Hard Disks (Size of Folders) Message-ID: Date: 3 May 88 10:15:33 GMT Organization: Carnegie Mellon Lines: 22 [tomc@mntgfx.mentor.com (Tom Carstensen) asks why, after copying a folder from one hard disk to another, the sizes are different] I think the difference you are seeing is the difference between the logical and physical lengths of a file. Somebody is going to have to verify this, but I think the block sizes on your two disks are different (entirely possible if each was formatted with its own initialization program). If disk A uses 512 byte blocks, while disk B uses 1K blocks, you will notice that, on the average, each file will use up an extra 256 bytes (calc: average space wasted on 1k block size is 512 bytes; average space wasted on 512 byte block size is 256 bytes; difference in extra space of 256 bytes per file). Does anybody know what the allocation block size is? Actually, the clump size could also complicate things. The clump size is the minimum number of bytes allocated each time a Write extends past the Physical EOF. Is there any program which could give us this information? Fedit, MacTools, your-favorite- program. This probably just confuses matters, but it gives us a goal and something to argue about :-) -Justin justin.vallon@andrew.cmu.edu