This hint does work on Snow Leopard, but it may not be apparent that it is working.

1. The "Event store UUIDs don't match for volume" and "Node requires deep traversal" messages are nothing to be alarmed about; it just means that Time Machine is out of sync with the fsevent queue and needs to rescan. This can happen for any number of reasons.

2. Some of the hints advise also updating the FSEventStoreUUID. I do not think this is a good idea. If the FSEvent queue is out of date, you really do want Time Machine to rescan -- otherwise it could miss files.

   Some users reported that they needed to fix FSEventStoreUUID to keep it from doing a full update. It may have had that effect, since it would cause Time Machine to think nothing has changed in that backup. But as soon as it scans a folder or drive for any other reason, it could still do an unnecessary file backup, if due to the other UUID issues it still thinks the old backup is a different drive.

3. I first applied the hint to update the Latest SnapshotVolumeUUID. I started the backup, Time Machine reported (after doing the full scan) that it wanted to backup an amount equal to the entire drive. I let it run for awhile, just in case, but quit it after it was clear that it really was backing up way too much.

4. I then applied the hint to recursively change the UUID in all of the backups. I started the backup, but again Time Machine (after full scan) reported it wanted to backup the same amount of data. So I canceled it.

5. Next I tried changing the UUID to be in hex, with the trailing 00. It still wanted to backup the same amount of data, so I canceled again.

   In retrospect I do not think that was necessary. Another post says that the ASCII UUID is really the same as the hex version; the only difference is how it is displayed.

6. After hours of frustration and failed attempts, I gave up and let the backup run to completion. It only backed up the incremental changes!

That's the key: There is no way to tell whether the backup is really a full backup or incremental without actually letting it perform the backup. There are no log messages or Time Machine displays that will reveal the difference.

My conclusion is that in Snow Leopard it is necessary to update the UUID on all of the backups (but I'm not 100% sure of that), but it isn't necessary to do anything more than that.

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