Maximum number of files in a folder ?

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Level 1

44 points

Maximum number of files in a folder ?

Hello, what is the maximum number of files in a folder OS X can handle ?

I used a file recovery software called FileSalvage to save some files of an external 300GB with a corrupted disk directory (unable to repair with the usual repair/recovery programs).

FileSalvage recovered about 435,000 files and sorted them by extension in individual folders, unfortunately it does not recognize the file names and just sequentially names the files per extension.

The .jpeg, .gif and .html folders had up to 75,000 files. After recovery the external FW drives started to behave very strange, unresponsive, just hanging, time-out. I tried on a Mac Mini, iMac G5, an iBook and PowerBook, OS X 10.3.9 and 10.4.3, FW400/800 and USB 2.0 interface, they all had pretty much the same failure mode after a while.

Running Disk Utility on the drives with the recovered FileSalvage folders showed a corrupted directory (invalid file count) and unable to repair, although I could copy most of the folders of the disk (deleted the folders with more than 10,000 files per folder).

I suspect that File Salvage copies more files in a folder than OS X allows, causing unpredicable problems.

Any ideas ?

iMac G5 2.0/1.5GB/250 GB, Mac OS X (10.4.3)

Posted on Nov 16, 2005 11:41 AM

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Answer 1

biovizier

Level 5

7,931 points

Nov 16, 2005 12:20 PM in response to Tom Gerkens

From " Mac OS X: Mac OS Extended Format volume and file limits"

"Maximum number of files (or files and folders) in a folder … up to 2.1 billion"

According to a note in the document, the above is subject to the drive's size (maximum 16 terabytes in "Tiger") and block size, ie. the number of available blocks.

So it would appear that the number of files you mentioned would be well within theoretical limits, although I suppose there could be a bug in some other part of OS X. Otherwise, maybe there is a problem with the drive...

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Answer 2

Tom Gerkens Author

Level 1

44 points

Nov 16, 2005 12:27 PM in response to biovizier

Hmmmh .. intersting.

I don't think there's a problem with the drives (four of them, all less than three months old). I also used three different external cases, and different FW and USB cables.

So far I am only able to trace it down to the FileSalvage folders. I'd like to believe that's the problem but I am not sure.

There's quite a bit of talk of failures on 10.4.2 and .3 with external FW drives but I have had similar issues with 10.3.9, I guess what I am experiencing is different.

Since I deleted the Folders with over 10,000 files, it seems to run fine. It just takes hours every time I need to copy. An incredible wast of time.

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