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Time Machine keeps reporting found thousands of changes before backing up

I recently "started over" with my Time Machine (TM) backups as I upgraded to Monterey and TM seemed to have problems with the pre-existing TM backup (it just wouldn't back up.) So I started over and the new backup initially worked for about 3-4 backups. And then TM began to hang. So, following the direction of an Apple Support rep, I re-confirmed my drive (in TM) that I was using for backup and it again began working as expected. But now the newest and latest boondoggle is when the backup session begins, TM laboriously reports its finding thousands and thousands of changes, counting seemingly every change one-by-one and the process is taking FOREVER. In this current session, it reporting over 115,000 changes which took over an hour and shows as about 20% in the progress bar. Now its copying files at about 30% done in the progress bar, with 250 megs copied and it estimates about 15 minutes remaining. And we all know Apple time estimates are ALWAYS way off.

I would think this counting of changes would maybe happen once or maybe twice but no, it happens every time TM begins its backup session. I have had Macs for over 30 years, started using TM when it first came out and have used TM backups to restore drives and I've NEVER seen TM be so slow. And this is 2017 iMac, which by the way, is the slowest Mac computer I've ever worked with.

Can anyone tell me why this counting of changes occurs? The only recent change I can account for is the installing of a small software program (17 megs) and a few emails. I have also deleted a couple of large files but certainly TM doesn't see a single deleted 3 gig file as 3,000,000 individual changes? This whole Time Machine backup process is getting old!


BTW, my backup drive is USB 3.0 and formatted to Mac OS Extended with more than 70% of the 2 TB available. Thanks!

iMac, OS X 10.11

Posted on May 4, 2022 7:21 PM

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14 replies

May 8, 2022 12:19 PM in response to ku4hx

Yes, that's what I meant when I said I "re-confirmed my Time Machine drive that I was using for back up." The force worked pretty smoothly the first time I did it -- and pretty quickly too-- but has resorted (back) to the lengthy back ups. It's like it forgets it has already done a prior back up. And its doing it again: a more-than-3-hour back up and it's telling me it has 3 more hours to go (at 36% done).

Jun 25, 2022 10:01 AM in response to Alwill

We are just other users like you and Apple support is not here.


Why are you waiting three days to do the next backup? The Time Machine drive should be left connected to the Mac, so that it can do hourly backup.


If it doesn't help to allow hourly Time Machine backups, then perhaps there is something else wrong or.... you have installed some type of Cleaning, Optimizing or AV-ware that is causing a problem.


At this point, we might be able to see a problem if you run EtreCheckPro and then post back here with the report.

to get EtreCheckPro from the developer, go to > https://etrecheck.com

to post your report, see > How to use the Add Text Feature When Post… - Apple Community

Jun 29, 2022 3:52 PM in response to den.thed

The report below says the TM auto-backups are disabled. They are not. Two days ago, I had turned auto back up off when an auto back up started and eventually, about 15% into the back up, TM just froze for probably 20 minutes and seemed unable to proceed (no beach ball though.) So I stopped the TM process, clicked off the Auto backup and shut down. Today I ran the EtreCheck test first thing to see if the failing drive comment would appear. It did. Then I clicked Back Up Automatically to "on" and re-conducted the test which reports TM Auto Back Up is off. Evidently a back up has to run? Not sure. Regardless, this is most current report. I am very curious to see some insight. Thanks!



Jul 1, 2022 3:23 PM in response to Alwill

Hi Alwill,


While a new Apple Silicon Mac would be a great upgrade, in an effort to extend the life of your current iMac, you could use an external SSD as your startup disk. It will make your Mac 10 to 30 times faster for storage, and in turn, make your entire Mac system much faster. For more info, instructions, and what external SSD to buy, please see: How to Setup and Use an External SSD as your Startup Disk on a Desktop Mac - Apple Community.


Cheers,


Jack

May 6, 2022 4:51 AM in response to Alwill

There are hundreds of processes running all the time creating small changes all the time. If you go far enough back in time, you'll see this.


If after letting it run to completion, then force a TM backup, you'll see far fewer changes as the historical period being drawn from is so small and recent.

May 12, 2022 6:13 AM in response to Alwill

And it's doing it again: TM has started a new session and is finding thousands and thousands of changes (which take an inordinate amount of time) before moving to actually backing up. Even though I (once again) forced a TM backup, which worked for oh, two more TM back up sessions (IOWs, like it should), before going back to the apparently finding changes regiment and TAKING HOURS to backup.


Got any other suggestions? I guess Carbon Copy Cloner is in my future...

Jun 25, 2022 9:32 AM in response to Alwill

Just checking in (Apple Support are YOU ever responding??) Getting the same: reporting there are thousands of changes, then going thru a backup/copy regiment which takes HOURS. Currently, TM tells me its copied around 1.2 gigs (and climbing) at 35% done and approximating will take two more hours, which we know is always off.


I know I haven't made 1.2 gigs of changes since the last backup was done 3 days ago. Oh yeah, which took almost 3 hours. Apple, this is getting OLD.

Jun 26, 2022 6:54 PM in response to den.thed

I have seen instances where Apple reps have remarked on various issues. I was hoping this would be one of them.


And I don't wait three days to do a backup: my TM is set to automatic. I can get on my iMac every so often and TM will not run. But if I'm on the device for say, an hour, then TM will start (which is weird as my usual experience with TM is it will start almost as soon as I fire up the device.) So every 3 days or so, I'm on the device more the device an hour and then I see TM running, with TM reporting changes which typically amount in the thousands. This take roughly an hour. Then TM will start copying, which takes roughly 2-3 hours.


I do have the free version of Malwarebytes installed, but nothing else. Malwarebyes was recommended by an Apple support rep when I called Support about how slow the iMac was to finally boot which takes like 2 minutes (which is another issue-- maybe related?) I don't think the free Malwarebyes version runs unless I force a scan. Anyway, she recommended it saying they have found it doesn't cause any issues like other programs.


Downloaded and ran etrecheck. It seemed to report a failing drive but not sure which one.


    Skip System Files: Yes


    Auto backup: No


    Volumes being backed up:


        Macintosh HD: Disk size: 1000.00 GB - Disk used: 218.58 GB


    Destinations:


        T*******p [Local] (Last used)


            Total size: 2.25 TB


            Total number of backups: 15


            Oldest backup: 2022-01-16 17:02:46


            Last backup: 2022-06-25 12:55:22




Performance:


    System Load: 1.60 (1 min ago) 1.74 (5 min ago) 1.89 (15 min ago)


    Nominal I/O usage: 0.09 MB/s


    File system: 36.01 seconds


    Write speed: 67 MB/s


    Read speed: 98 MB/s


Jun 27, 2022 7:13 PM in response to den.thed

Before I provide the full report, I feel the need to relay that I had turned off the Time Machine Backup Automatically option and ran EtreCheck TWICE and it did not give any indications of issues. In fact, I only had minor issues.


But then I turned TM's Backup Automatically on again and ran EtreCheck, and TM was NOT running, the report come back with seemingly drive speed issues. Why would that be??

Jul 1, 2022 2:35 PM in response to den.thed

Well that's a new one. After 33 years of owning Apple computers, this is first time I've heard "entry level." Yeah, I knew it wasn't top of the line but I've NEVER had any issues like this with any Mac and I've challenged them all. When I spoke with a Mac Support Rep over a year ago complaining about how slow this iMac, she didn't refer to as entry level and that I should only use it to surf the web and maybe email.


I guess an M1 Mac-mini is looking like it's in the future. Thanks for all your help and insight.

Time Machine keeps reporting found thousands of changes before backing up

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