[PaperNotes]

I just started using Time Machine last night. To test it out I made it do a full backup of the directories I want included and after that I deleted several text and media files from assorted directories. The next time Time Machine made a backup it did not reflect the changes and still shows the files that I have deleted. I'm still waiting for the changes to show up in Time Machine.

Is this usual behavior and how accurate is TM in reflecting changes?

[FireWire]

I think Time Machine only performs one backup per hour (hourly backups). If you make change before the next backup, TM won't know what happened in the mean time. So, if within the same hour, you create and delete a file, you won't be able to recover it...

From Apple - Mac OS X Leopard - Features - Time Machine :

Every hour, every day, an incremental backup of your Mac is made automatically as long as your backup drive is attached to your Mac. Time Machine saves the hourly backups for the past 24 hours, daily backups for the past month, and weekly backups for everything older than a month. Only files created and then deleted before the next hourly backup will not be included in the long term.

Personally that baffles me because I remember reading that TM tapped directly into the file system manager to know exactly what changed and when.

[zerostar]

Originally Posted by PaperNotes 

I just started using Time Machine last night. To test it out I made it do a full backup of the directories I want included and after that I deleted several text and media files from assorted directories. The next time Time Machine made a backup it did not reflect the changes and still shows the files that I have deleted. I'm still waiting for the changes to show up in Time Machine.

Is this usual behavior and how accurate is TM in reflecting changes?

So you want it to remove those files from the backup drive too? This would defeat the whole purpose of a backup would it not?

What happens if you accidently deleted a file and went to your backup and it was gone there too? Not very effective is it?

[Person Man]

Originally Posted by FireWire 

Personally that baffles me because I remember reading that TM tapped directly into the file system manager to know exactly what changed and when.

Yes, but since Time Machine operates on the file level, it copies all files that have been changed since the last backup, rather than making links to already existing unchanged files in its directory structure.

You cannot copy a file that has been created and then deleted between backups, because even though the log will show that a file has been created and then deleted, there will be no file to copy because it was deleted before it could be copied.

[Mrjinglesusa]

Yeah, I'm not sure your test was all that great. How often will you create and delete a file within an hour? And if you delete it within an hour of creating it, you probably don't need or want it anyway.

To answer your question, no, TM is not inaccurate.

[PaperNotes]

After several hours of TM doing its thing every hour I am still not seeing an accurate representation of files on the chronological time scale. For example:

Folder "Documents" contained 11 Word documents at 12AM. I deleted three documents afterwards that I am sure I do not need. They can disappear forever. I am now left with 8 documents.

Time Machine does another backup at 1PM. The backup for this time shows all 11 Word documents even though I deleted three. Time Machine should only show me these files as existing in the 12AM backup, not at any point on the time scale after.

Every hour after that the backups still show all 11 documents. Manually removing these documents from the external hard drive isn't allowed either.

So I'm left wondering if this is a common bug?

[TETENAL]

No, that's not a common bug. It works for me as expected.

[besson3c]

I'm not sure how much I trust TM either, although I can't make a case right now...

If your objective is to delete these files, there is a way to do so directly from your external drive.

[Person Man]

Originally Posted by TETENAL 

No, that's not a common bug. It works for me as expected.

It works as expected for me, too. If I delete a file, it does not appear in subsequent hourly backups.

But when I go back to that day a few days later, the deleted file appears, because Time Machine consolidates all the hourly backups into one daily backup. And then after a month, the daily backups get consolidated into weekly backups.

[MacosNerd]

Originally Posted by Person Man 

It works as expected for me, too. If I delete a file, it does not appear in subsequent hourly backups.

But when I go back to that day a few days later, the deleted file appears,

That's how it works for me and to be honest that how I expected TM to work.

A full backup has everything but then the hourly incremental backups show current state. Heck, If delete something and it disappears completely out of TM then what good is that. I want Time Machine to maintain a back of my data. If want the copy of my data to mimic the actual, I'll go with a RAID 1 solution.

[PaperNotes]

Originally Posted by Person Man 

It works as expected for me, too. If I delete a file, it does not appear in subsequent hourly backups.

Then mine definitely has a bug. I formated the external drive twice and the bug has reproduced itself every time. Will have to wait for software updates before TM works proper for me.

[Hal Itosis]

This tip/thread from macosxhints may prove interesting:
Compare Time Machine backups to original drive

[PaperNotes]

Thanks for the link. Bugger.

[Kevin]

*sigh* more signs of it being a beta OS.