Q: Time machine backups take way too long

OK, I timed a Spotlight re-indexing operation. 24 min. Seems to be fine. (approx. 270,000 folders and approx. 1.1 million files on a 500 GB disk.

Started a backup at 9:52 EDT. It's still going now at 10:00 EDT (UTC-0400). It's been in the . . . oh, just made it to 41.5 MB of 42.5 MB. Before that it behaved as usual: A long time calculating changes with high CPU usage, a shorter time preparing items, then the 30 KB (+/- a few) our of 40 something MB for a long time with lots of up and down writing to disk and at time very high CPU. Now it's 43.4 MB of 43.4 MB. What the donkey kong is it doing? Had some significant disk activity, now no disk activity, but high CPU usage.

Maybe it's time to bite the bullet and upgrade. But I hate not being able to downgrade in case of a problem, though I'm been told both it can be done to it can't be done to it can be done, but only with some difficulty. (I recall the horror of not being able to down grade iOS on my iPod a while back to fix the video scrubbing problem. Very upsetting.)

Or maybe my a new iMac. Then I could tryout Final Cut!

Still at 43.4 MB of 43.4 MB at 10:18 EDT. Maybe an OS upgrade caused this, but I don't recall doing one recently enough. Is there an upgrade history kept on the machine?

Now it's doing a 2nd pass (round, backup, whatever you want to call it) at 10:18 EDT.

Ugh.

I forgot one thing. I first noticed the problem quite a while ago when I noticed that the backup clock menu icon was spinning much more often than usual. I was also using this backup disk to store some large files. I thought maybe that was the problem. I tried it on another drive, but with the same results. (It too had some large files on it, outside of the backup folder.) So I bought a spanking brand new hard drive and dedicated it totally to Time Machine. At first I was getting short backups, about 6 min. each. This still seemed longer than it should be, but much better than half an hour! But then it got to be 12 min. Then 30, and now almost an hour. No, it's not because the backup disk is filling up. It is a 3 TB disk and has 2TB free on it. So maybe TM is doing something screwy on the backup disk and this creates an increasingly entangled web of hard links.

I still have to go through the pondini website again, just to be sure I didn't miss anything. There's a cnet page with some TM troubleshooting advice on it (http://reviews.cnet.com/8301-13727_7-20116246-263/tackling-time-machine-slowdown s-in-os-x/) but most of it seems n/a to my situation. I have to try a safe boot TM backup. Will report back when I do.

Thanks all for your efforts.

I think TM is just being hyper-conservative with the padding.

AEF

The padding is to pre-emptively allow for any new files that appear during the backup. Suppose you copy a 40GB video from another drive, or download some huge file. With padding you are less likely to fill up the disk before the backup completes.

Finally got it fixed. \(^_^)/ The cure? Start a process that attempts to create a partition that crashes part of the way through. (I was trying to create a new partition to load a fresh install of 10.6.8 to see if that would also have the problem.) Somewhere in the middle of it I got the Gray Curtain of Death -- a kernel panic. After that I did a Safe Boot. I ran a backup. It took 2m50s. Not bad. Booted regular and now my backups take seconds -- sometimes as little as 4 sec. I think one or two took 5 min. and 10 min. But other than those they're always less than a minute.

Does anyone have any ideas as to why this worked?

If this happens again I will do a complete Repair Disk operation. I did do a Verify Disk (on the system disk) and it passed, so I'm not sure that would work. It's something to try. And if that doesn't work I'll do the partition trick and hope it crashes!

AEF

Oh! The other thing is that my Mac is working much better now. A lot fewer beach balls, even when opening iMovie.

Here's my recommendation:

Boot from CD or DVD and use Disk Utility to do a Repair Disk on your system disk (internal hard drive).

If that doesn't fix it, make a new partition almost as big as the free space on your hard drive and hope you get a kernel panic.

I agree. You could hide the frequency of backups setting under the old "Advanced" button.

OTOH, my backups usually take seconds now, and my machine is running much better.