Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

kat.hayes

macrumors 65816
Original poster
Oct 10, 2011
1,448
52
My Macpro has been freezing and I have to cut the power. I'm worried that this could damage my other internal drives.

1. Can you eject internal drives like you can an external? Is it a bad idea for any reason to do this?

2. I was able to plug in my external and do a Time Machine backup. It is set to not copy application files. Can this copy over any of the problems I might be having that is causing the Mac to freeze?

Thanks.
 
1. Semulov can do this not harmful procedure.

2. If you EXCLUDED the Applications folder from being backed up, and the application(s) you determined to be responsible for your freezing issues are in that folder, those applications will not be backed up.

If you want to enhance the performance of your Mac, be sure to check these two articles, do not just use applications, that promise to do it for you.
 
Thanks for your reply.

1.) Does Time Machine also backup the OS? Does it only do this if you have it set to backup applications?

2.) Since it is crashing, and did so while I had files open, is there a way to determine if any files were corrupted? As an example, I had Lightroom open with hundreds of images when it crashed twice.

Thanks.
 
System crashes and freezes can indeed trash hard-drives - or at least the data on them. This is pretty rare tho. The HDDs themselves do not crash when the system crashes. The system crashes and the drives finish writing out their buffer contents (in some milliseconds) and then just sit there waiting for further instruction. When the system is rebooted and the HDDs get an init command they close the file and write the check. If the drive lost power under such conditions it goes through a verify process and closes the file and writes the check on next power up (depending). Some may have noticed that after a system crash especially one where the power turns off to the drive bus, the drive or drives spend quite a bit longer initializing and/or house cleaning - causing slower boots and busy HDD access lights for longer periods than otherwise usual (sometimes even taking 10 or 20min to calm down). The OS works in tandem with this information to place a recovered folder in the trash with whatever files might be in question (depending).

This is normal and part of the drive firmware and saves us A LOT of troubles with the file system and file integrity. For this reason you don't need to worry about ejecting drives or anything like that. Of course if you know before hand the system is going down - which is the case with many developers during debug cycles - then it's a good idea to close al files and if you can take the drives off the bus by ejecting them or un-mounting them first. ;)


By default TimeMachine backs up your entire OS as well as the Recovery Partition with the exception of a few common cache and temp folders. From the defaults you can add or remove drives and folders from the exclusion list.


There's no easy way to determine if the files are corrupt without opening them. You can do that with some utilities which will check the data against the written check. DiskUtility's Verify will verify file allocation tables and some other stuff. The time a file level verification takes up depends on the speed of the drive, the number of files, and of course the application speed. For a full 3TB drive this can take hours and hours. There may be some utility that can just verify specific folders but I haven't paid enough attention to know what they are. Have a search.
 
Last edited:
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.