Mac OS X 10.4.1: Spotlight: Tips for faster searches, problems with .DAT files; more

CNET staff

Sept. 2, 2009 11:34 a.m. PT

5 min read

Spotlight: Choking on Finder.DAT files? We've received scattered reports from readers indicating that Mac OS X 10.4.x's Spotlight may have problems indexing and searching for Finder.DAT files -- data files usually containing text created by an older Classic Mac OS application like ClarisWorks or spawned by another third-party application.

MacFixIt reader Dave Stephens offers a case example:

"I thought the FireWire hard drive was somehow Spotlight-incompatible. Not so. But I suppose Spotlight doesn't like Finder.DAT files at all. It hung on indexing, first giving a bogus hourly that got bigger and bigger but never went away. So I made the volume 'Private'. When I made it 'not private' again, it simply hung.

"So then I deleted the only files I knew were superfluous, the Finder.DAT files that were everywhere (from a ton of CF Card derived folders).

"I don't know where they came from, but I think I had a third party utility that created them, or perhaps they are a remnant from the Nikon camera that made the containing folders. In any event, when I deleted all of them, suddenly Spotlight was able to index the volume it couldn't before."

If you're experiencing a similar issue, please let us know.

Tip: Paste search strings We previously noted that one of the biggest user gripes with Mac OS X 10.4.x's Spotlight is a sometimes dramatic pause that occurs after typing one or two characters, as Spotlight begins searching immediately for all data containing those letters.

MacFixIt reader Tracy Valleau offers a simple tip for avoiding this slow-down -- typing the search string in an open text field then copying and pasting the text into the Spotlight search field.

Tracy writes:

"To dramatically speed up Spotlight or Find, just paste the search term in, instead of typing it."

Preserving Spotlight comments when burning to non-HFS volumes (CDs/DVDs etc.) By default, Spotlight comments are not preserved for files backed up to removable media.

This is because Spotlight comments will only be stored on CD's burned as HFS (also known as "Mac OS Extended"). Other filesystems (such as UDF, ISO9660, etc) aren't capable of storing the metadata, and Finder-burned CDs and DVDs use these filesystems for cross-platform compatibility.

MacFixIt reader Joshua Ochs notes a method that will allow Spotlight comments to be preserved when backing up data to removable media, other non-HFS volumes:

"One way around this is to create a disk image with the files (which would be HFS ), and then burn the disk image to a CD, which would preserve the comments. As a bonus, you can preview it before burning to make sure everything you want is there."

Disable Spotlight for backup target volumes Users should disable Spotlight for backup target volumes (by using the "Privacy" tab of the Spotlight pane in System Preferences) before beginning the backup process to prevent live indexing as the files are copied.

Failing to do so can result in failed backups, significant performance issues, and other problems.

MacFixIt reader Thomas reports one such issue when using Retrospect to perform a routine backup:

"When trying to create my first bootable backup since installing Tiger, Retrospect stalled in the middle of the action with several errors.

"I concluded that Spotlight was indexing the clone-partition while it was written. When Retrospect wants to copy the files it finds newer versions already present that it can not overwrite because they are 'in use.' This appalls Retrospect so much - it doesn't even want to finish the rest of the

"So I used the Privacy-Tab of Spotlight's preferences to kick the backup-drive out of Spotlights universe - and the [Duplicate]-process went fine and complete this time."

Invisible file limitations MacFixIt reader Adam Williams shares some insight gleaned from an Apple employee on why Spotlight will not find some invisible files:

"I talked with a buddy of mine that works at Apple about the spotlight invisible file issue. More specifically i was trying to locate files in usr directory and other system directories.

"He told me this is why spotlight wasn't finding invisible files: mdimport (the process used by Spotlight for indexing) has a built in list of privacy folders on top of those defined in the Spotlight System Preferences pane. This prevents Spotlight from indexing these system folders. He told me it is apples wishes to keep system files from appearing to the common user who might type in a phrase that could pull up system files that a less experienced user could harmfully alter.

"There is also a noted issue about spotlight performance he brought up. Anything spotlight has indexed, will be reindexed every time file is modified. With how often system is changing it's files, caches, installing updates, etc. Image spotlight spiking CPU constantly for this. The speed hit would be hideous. A user can force an index of system folders using the mdimport command, but it is not recommended at all. He did inform me that Spotlight reverts to filename/catalog b-tree search if an index isn't present. However, it still follows it's privacy defaults so still ignores system folders."

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