files AWOL in finder

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Level 1

129 points

files AWOL in finder

OSX Lion 10.7.3, 6b ram, 1TB internal drive, 2.8ghz IC Duo, 40gb, 400gb, (firewire) 500gb and 1TB (USB) extermal drives.

Veteran Mac user, comfortable in terminal

Situation:

large fileset on external drives suddenly disappers from finder.

open terminal, cd into directory, issue 'ls -la'

files scroll by in terminal view

files appear in open finder window

given some uncertain set of circumstances, files disappear in Finder again

The first time this happened, I immediately thought the HD was going bad, so I tried to use Disk Utility to make a dmg backup. DU fails with 'insufficient permissions' even after multiple permission rebuild attempts.

Using SuperDuper, I was able to make a file-level backup. SD is now set to back up the working external drive (40gb) once daily.

However, the disappearing files exhibit the same behavior in the SuperDuper-maintained external as in the primary external HD.

I have not migrated the filset to the internal drive and am reluctant to do so.

One more salient point: when this error first occurred, the 'vanished' fileset actually had a local backup in place, something like this:

EXTHD/FILESET/

EXTHD/FILESETBAK/

when I examined FILESETBAK, the directory appeared empty in Finder but running ls -la returned the file display to the expected state.

the non-hidden filecount in these directories is roughly 14,500 files, each under 1 mb in size.

Any insight is appreciated.

Posted on May 2, 2012 4:56 PM

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Answer 1

Linc Davis

Level 10

209,547 points

May 2, 2012 6:00 PM in response to mike whybark

I've never heard of this before, but almost certainly, you're triggering a bug in the Finder by putting too many files in one folder. In one way or another, that's been a weakness of the Finder for many years. Try distributing the files into subfolders, so that you have no more than a few hundred items in any single view.

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Answer 2

mike whybark Author

Level 1

129 points

May 3, 2012 7:54 AM in response to Linc Davis

Apple publishes support for up to 2.1 billion files in a folder under HFS, so I am skeptical of this explanation.

http://support.apple.com/kb/HT2422

The process I am directing toward the file collection may make it impractical to chunk the fileset, unfortunately.

Further observation of duplicate instances of the 14k file count folder commonly display a long delay to render the files in a finder window. Presumably whatever process is ongoing when one of these folders is opened for the first time failed somehow in the problem instance I describe.

What is exceedingly fishy and kind of dangerous seeming is the apparent simultaneous disappearance of two identical filesets. I had a batch process running in another logged-in user ID when the files appeared to disappear, and the batch process was apparently reliant on the Finder directory info rather than the info accessible via terminal, as the process halted in an error state reporting no files.

TO DO:

verify that the outboard drive is HFS

examine to possiblity of programatically chunking the fileset

examine the possibility of enabling directory traversal for batch process

even if the fileset can be chunked and then processed that may not be acceptable for the output, as the files need to reside in a single output directory.

Anyway, thanks for your input. Backups seem to be working OK, so things are moving forward even with the apparent file system volatility.

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Answer 3

Linc Davis

Level 10

209,547 points

May 3, 2012 8:16 AM in response to mike whybark

Apple publishes support for up to 2.1 billion files in a folder under HFS...

That's irrelevant. I'm not saying you can't put that many files in a folder. I'm saying the Finder may not display them properly in a window, because of a bug.

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