Significant slowdown of Time Machine after upgrade to Lion; indexing problem

Question

After upgrading to Lion over the weekend I notice a significant slowdown of Time Machine processing.  I assumed the first backup or two would take some time but it's been a couple of days.  The process always hangs up at the "Indexing backup" stage.  It takes a couple of hours to finish.
I found several threads relating to slowed down backups on Lion, most seem to hang at the "Preparing" stage (not the same symptom) but I did find some good diagnostic pointers.  I installed the widget to see what kind of messages were being produced and found a few dozen "Waiting for index to be ready (100)" messages at the end of the stream.  Further research - this is not a good thing :-)  It seems a couple of such messages can be ok, but this many usually indicates a problem.  I'm going to discount the possibility of a hardware failure because everything was perfectly fine up to the point I made the upgrade.  Plus the prepare and copy seem to proceed at the expected speed (I watched the most recent cycle just to be sure).
Here is the full message log (it's still running at the moment):
Starting standard backup
Attempting to mount network destination URL: afp://Paul%[email protected]/Paul%20DiMarzio's%20Tim e%20Capsul
Mounted network destination at mountpoint: /Volumes/Paul DiMarzio's Time Capsul using URL: afp://Paul%[email protected]/Paul%20DiMarzio's%20Tim e%20Capsul
QUICKCHECK ONLY; FILESYSTEM CLEAN
Disk image /Volumes/Paul DiMarzio's Time Capsul/Paul DiMarzio’s MacBook Pro.sparsebundle mounted at: /Volumes/Time Machine Backups
Backing up to: /Volumes/Time Machine Backups/Backups.backupdb
12.15 GB required (including padding), 490.69 GB available
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
Waiting for index to be ready (100)
I further found the advice and instructions on how to run the disk utility on the sparsebundle.  I did a verify and repair, and the results came back that the drive appears to be ok (it did not say that it explicitly repaired anything).
But the problem remains.
I use a 1TB Time Capsule with plenty of free capacity (only half full).  The TC and my MacBook are both hardwired into the home network, networking speed has never been an issue.
I'd sure hate to delete the backup file and start from scratch, there's over a year's worth of data there and I have, occassionally, wanted to go in there and pick up a downlevel or subsequently deleted file.
Any advice on other diagnostics or repair options to take?  Thanks!
Paul

Answer 1

After posting I decided to keep trying to slog my way through the troubleshooting guide.  Some of the steps are beyond my understanding but I did follow the advice in #D2 to delete the .Spotlight-V100 file from the sparsebundle.  That action does seem to have done the trick, the backups are now completing in normal time.  I ran a couple just to be sure.  I've verified the backups with BackupLoupe and entered the Time Machine, all appears to be in order and as expected.  The only odd side effect is that the backup volume is no longer ejected after completion but that might just be an artifact of all my mounting/de-mounting and playing with Finder.  Anyway a very small price to pay for what looks to be a working system again.
Hopefully the good behavior will last through a few days and a few reboots :-)
ps - if you're reading this and don't know about the troublshooting guide it's here: http://web.me.com/pondini/Time_Machine/Troubleshooting.html (thanks pondini)