We've found Time Machine incredibly, incredibly slow on the initial backup. Even with gigabit ethernet, it would backup may 3GB after 2 hours. With the way we use machines at work, it would just start over all the time. "Macrumors.com":http://forums.macrumors.com/showthread.php?t=379066 has some advice about what to do:
* Turn off Time Machine
* If you aren't using a Time Capsule, "don't":http://blog.stevex.net/index.php/2007/11/04/time-machine-and-slow-first-backup/ let Time Machine format the disk, do it yourself (not relevant if you have Time Capsule since these are already formatted). "Gizmodo.com":http://gizmodo.com/gadgets/apple/leopard-disk-utility-format-issue-screws-with-time-machine-but-theres-an-easy-fix-316573.php explains the problem is that with PC formatted drives, Time Machine doesn't format them correctly, so you have to erase with Disk Utility and then format as a Mac drive with Disk Utility as well.
* Exclude the disk from spotlight indexing and don't start the initial backup while spotlight is doing the initial installation. "Discussions.apple.com":http://discussions.apple.com/thread.jspa?threadID=1430223&amp;amp;tstart=0 emphasizes that you ahve to turn privacy tab off of spotlight for all disk involved. Go to System Preference>Spotlight>Privacy and drag to all the disks involved. Both the Time Capsule and the local hard drive.
* Turn off virus checking for sure! (I think this is my problem with my MacBook Air. I use clamav). This sped up the system 10x for the user.
* Other folks report that unmounting Time Capsule from Finder might help, but that's unclear.
A 90GB system should take 120 minutes to do.
On a different front, "vitarara.org":http://www.vitarara.org/cms/node/149 points out that you need to delete the ".inprogress" folder using the Finder on your Time Capsule and then restart Time Machine. You should get 12-14MB/second on a wired connection.
For "Time Capsule":http://discussions.apple.com/thread.jspa?messageID=7110199 itself, people are finding that it takes 8 hours to backup 150GB and they use the wired connection. It is slow apparently intentionally to keep the computer being backed up fast. Not what folks want. I suspect, most folks would want to dedicate it because 8 hours of waiting just doesn't make sense for most folks with laptops. Means they would be without a computer for a day in essence at work.
Others are reporting that the "Time Capsule":http://discussions.apple.com/thread.jspa?threadID=1430223&amp;amp;amp;tstart=0 seems to slow down over the day and they need to do a restart. *It seems to me that what is probably happening is the 802.11 wifi is slowly hunting down. That can happen, the Wifi slows down if there is interference and never goes back up, so it sounds like regular reboots of slow Time Capsules matter*
Some other problems include "backup corruption":http://discussions.apple.com/thread.jspa?threadID=1503192&amp;amp;tstart=0 on MacBook Pro on wireless and then will hang on preparing backup...
As an aside the theoretical speeds for a Time Capsule should be "11.76MBps":http://discussions.apple.com/thread.jspa?threadID=1471381&amp;amp;tstart=15 on Gigabit ethernet and 10MBps on 5Ghz. I've never actually gotten this.
Finally some folks suspect that the latest firmware "7.3.1":http://discussions.apple.com/thread.jspa?threadID=1471381&amp;amp;tstart=15 is just slowing things down and "some":http://discussions.apple.com/thread.jspa?threadID=1502277&amp;tstart=30 have found that a hardware reset by pushing the factory reset on the back realy does help. He was getting 0.2MBps until he hit reset then got 2MBps on an 802.11g connection.