I just got a new external hard disk, and initialized it as a new Time Machine disk. My boot drive has about 78GB on it, The first, full backup took about 70 minutes. I expected that after this, backups would be quick, but they're all taking about 30 minutes, even though I'm not doing much. The Console log reports that it's doing deep traveral every time:
6/9/13 6:23:32 PM
Node requires deep traversal:/ reason:contains changes|must scan subdirs|fsevent|
and it's backing up almost 200K files each time:
6/9/13 6:32:14 PM
Copied 109610 files (17.3 MB) from volume Macintosh HD.
6/9/13 6:42:00 PM
Copied 86516 files (3.4 MB) from volume Macintosh HD.
I have BackupLoupe, and examined what's in each snapshot. Lots of things in /usr, /Applications, /System, and /Library are getting backed up every time. When I drill inside, I see that everything that's being backed up repeatedly is an alias.
They're not taking up much space, but I think this is what's making the backups take so long. Why is it wasting time on all these aliases?