Overlapped extent allocation - wtf?

[cleo]

My iMac has been cranky ever since I installed 10.2. Lots of spinning beachballs, abrubt Finder relaunches, etc. Tonight I finally got around to running Disk First Aid. I got about three dozen "overlapped extent allocation" errors that weren't fixed after trying to repair the disk multiple times. Some other errors were fixed, and so far thing are running a bit more smoothly. But what is this "overlapped extent allocation" stuff all about? Do I need to try to fix it? How?

 

[strider42]

Re: Overlapped extent allocation - wtf?

Originally posted by cleo
My iMac has been cranky ever since I installed 10.2. Lots of spinning beachballs, abrubt Finder relaunches, etc. Tonight I finally got around to running Disk First Aid. I got about three dozen "overlapped extent allocation" errors that weren't fixed after trying to repair the disk multiple times. Some other errors were fixed, and so far thing are running a bit more smoothly. But what is this "overlapped extent allocation" stuff all about? Do I need to try to fix it? How?

I'm not absolutely sure, but I'm thinking diskwarrior could probably fix this. usually if there is an error DFA can't fix, diskwarrior can.

 

[Hemingray]

Overlapped extent allocation sounds like the catalog file has data telling the computer that File A has data in blocks 1-5 and File B has data in blocks 4-8. Both files have been allocated a same portion of space, so they're overlapping.

That was a total guess. I dunno if that's what it really means, but if it's the least bit accurate you'd better do what strider42 said. Or, did you try booting from the OS X CD and run DFA from there?

 

[cleo]

Yeah, I booted from the Jag CD. Bleh... I really don't have the cash to buy software right now (yes, I know I should bite the bullet and buy a disk utility, but I don't want tooooo) </whine>. Would reinstalling Jag fix the problem? There's not much on that computer right now, anyway - would be a snap to backup.

 

[Hemingray]

If the damage can't be fixed with DFA and you can't afford a disk utility program, you should back up everything and wipe your drive, then reinstall.

When you installed Jaguar, did you just update? Or did you archive and install? After you wipe your drive, installing Jaguar fresh should definitely show an improvement in performance.

One more thing you could try: Boot your computer into single user mode (hold down command+s at startup) and then at the prompt type "fsck -y" (without quotes). After it finishes, type "fsck -y" again, and keep doing that until it reports there are no errors. If the same errors keep popping up and nothing is getting repaired, then it's not working and you'll need to try the other methods. To exit, type "exit".

 

[FattyMembrane]

erasing the hard drive is the slacker's disk utility (i.e. my disk utility ) but if you don't feel like backing up all your data, count that option out. an erase and install of jaguar should take care of any software disk related problems as well as any fragmentation issues.