DiskWarrior running for 5 days now

Question

Here's my story.  My Timecapsule 2 TB WD Caviar Green HD failed.  It had/has roughly 1.25 TB of data in it so I tried data recovery software but it kept having an unmounting error.  I took it in to get repaired and they replied:  "A Gillware technician has completed the evaluation phase of the recovery process and determined that your drive is mechanically healthy, but will require a Tier-2 logical recovery considering the drive's catalog file is severely corrupted and will require us to try to figure out where all of the binary data resides within the drive."
The free quote they gave me for this evaluation was really expensive ($1200) and I'm a student so I got the HD back.  I found out that they had actually opened my HD but for reasons I don't understand, it didn't have an unmounting problem anymore!
Fast-forward to now, I've been running diskwarrior for 5 days now and it's been chugging along slowly at step 5 (as seen below).  It hasn't stalled because the "Speed reduced by disk malfunction" number keeps increasing (up to 26k+)  which according to the disk warrior website is the sign that it hasn't stalled.  My question is:  how much longer should I anticipate DW running for?  Has anyone else gone through a similar situation? 
Any advice would be much appreciated!  Thank you so much for your time!!!

Answer 1

The corruption of a drives catalog file is a logical error, not a mechanical one. A logical error can be caused by improper removal from a computer or sudden power loss.
One of the misconceptions that circulate on ASC is the idea that a journaled HFS volume can be corrupted by a forced unmount, as for example in a system crash or a power failure. That idea is false.
With filesystem journaling, when the volume is remounted after a forced unmount, the directory is automatically repaired, and files are restored to their previous state, using redundant information (the journal) stored on the drive. This is very well established technology, and for all practical purposes, it always works, unless the journal itself is corrupt due to a hardware failure in the drive or elsewhere in the data path. So if the directory of a journaled volume is found to be corrupt, the storage device hosting the volume has thrown at least one unrecoverable hardware error.
People who don't understand journaling will tell you to repair the corrupt volume with Disk Utility (if possible), or with Disk Warrior otherwise, and then go on using the drive as if everything is fine. That might have been good advice years ago, before the introduction of HFS journaling, when it was common for volumes to be corrupted as the result of forced unmounting. Today, because forced unmounts no longer cause that kind of corruption, it's relatively rare — or should be — and when it does happen, the implications are different.
My opinion is that when a drive throws such a severe error that a volume directory not only can't be restored by journal replay, but also can't be repaired by Disk Utility, that drive should no longer be trusted with data. It should be taken to a recycling center.
But even if you do choose to go on trusting the drive, if you have backups, you shouldn’t try to scavenge the directory with Disk Warrior. You should erase the volume and restore the data from your backups. Doing that is faster, safer, and cheaper than using DW. DW should be reserved for those situations where there are no backups, and even then, the drive should still be erased, or preferably retired, after the data is recovered.
Deric Horn, the head of filesystem engineering at Apple, gave a presentation at WWDC 2012 in which he stated, with regard to journaled HFS (starting at offset 3:18 in the recording):  
The journal means that you can pull power at any time, and your filesystem is still intact. There shouldn't be any data corruption or any volume corruption on that disk.
You can hear the presentation by registering for a free developer account with Apple and going to this page. (Eventually the link will break; if that's already happened, you'll just have to take my word for it.) Look for "What's New In The Filesystem" near the bottom.
If a poster on this site knows more about HFS than the Apple software engineer in charge of it, then the latter should be fired, and the former should get his job. Until that happens, I suggest you believe what Horn says.