What scenario could cause 7GB hourly Time Machine backups?


wardie

macrumors 6502
Aug 18, 2008
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It seems Time Machine is backing up just under 7GB of data every hour. Is there a specific scenario or two that might cause this to happen?
You got any virtual machines? I’ve found previously that TM doesn’t play nicely sometimes with the big VM files and hence any changes mean the whole VM needs copying again...
 
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Sal Collaziano

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Original poster
Nov 7, 2007
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You got any virtual machines? I’ve found previously that TM doesn’t play nicely sometimes with the big VM files and hence any changes mean the whole VM needs copying again...
No, this is a new computer and I'm not using any VMs. I wanted this one to be clean with no issues. But for some reason, every Time Machine backup is 6.85gb, 6.88gb or very close...
 

MC6800

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Jun 29, 2016
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You could also check if you have large recently changed file(s) using Finder's "All My Files", sorted by date.

I'd use Terminal and type "sudo fs_usage" to see just which files are being written during a session (stretch the window wide to see full pathnames).
 

Sal Collaziano

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Original poster
Nov 7, 2007
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When you go to "about this Mac" what does it show for hard drive use under the "Storage" tab?
I have 2.72 TB available of 3.11 TB...

You could also check if you have large recently changed file(s) using Finder's "All My Files", sorted by date.

I'd use Terminal and type "sudo fs_usage" to see just which files are being written during a session (stretch the window wide to see full pathnames).
I don't think I have "all my files" anymore as I'm on High Sierra. When I looked in Terminal there are just thousands of files scrolling so I'm not sure what to do there. The same exact scenario happens with my MacBook Pro and I figured getting a new computer and not restoring from a backup would fix whatever it is. I was wrong. It's not the end of the world - just very strange and kind of annoying. I wish Time Machine would just backup what has changed since the last backup an hour earlier...
 

Darmok N Jalad

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Sep 26, 2017
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When you go into Time Machine Preferences, and then click on "Options..." what does it say your estimated full backup size should be? For me, my backup says a full backup is 56GB, but my Time Machine backup is 74GB due to system and file changes over time. Usually when Time Machine runs, the backups are pretty small.
 

Sal Collaziano

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Original poster
Nov 7, 2007
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Royal Palm Beach, FL
When you go into Time Machine Preferences, and then click on "Options..." what does it say your estimated full backup size should be? For me, my backup says a full backup is 56GB, but my Time Machine backup is 74GB due to system and file changes over time. Usually when Time Machine runs, the backups are pretty small.
Mine is 396.78...
 

Darmok N Jalad

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Sep 26, 2017
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3.11TB - 2.72TB is about 400GB, so it sounds like your backup is ending up as the right size. It is odd that each hour 7GB is being moved around. I can only guess something is indexing your files, but it's hard to know. What makes up the majority of your storage--photos, videos, other?
 

danielwsmithee

macrumors 65816
Mar 12, 2005
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I’ve seen behavior like this out of TimeMachine before. It turned out to be a single corrupt file that every time TimeMache tried to copy it it crashed the backup process, then it would start backup from there and hit the same file the next time. It really would have been nice for a dialog to tell me which file was bad, but no I had disable backups on a folder by folder basis until I found it.

For me it was a corrupt video file in what was my iPhoto library at the time. I’d start by disabling backups of your media folders one at a time and see if you can narrow it down to specific large folder that won’t backup.
 

Fishrrman

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Feb 20, 2009
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Try either CarbonCopyCloner or SuperDuper.

Once a day with either should be fine.

And your backups won't continually "grow" in size.
 

Sal Collaziano

macrumors regular
Original poster
Nov 7, 2007
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Royal Palm Beach, FL
3.11TB - 2.72TB is about 400GB, so it sounds like your backup is ending up as the right size. It is odd that each hour 7GB is being moved around. I can only guess something is indexing your files, but it's hard to know. What makes up the majority of your storage--photos, videos, other?
Mostly photos, then videos...

Cloning rules OK?
Not sure what you mean...

I’ve seen behavior like this out of TimeMachine before. It turned out to be a single corrupt file that every time TimeMache tried to copy it it crashed the backup process, then it would start backup from there and hit the same file the next time. It really would have been nice for a dialog to tell me which file was bad, but no I had disable backups on a folder by folder basis until I found it.

For me it was a corrupt video file in what was my iPhoto library at the time. I’d start by disabling backups of your media folders one at a time and see if you can narrow it down to specific large folder that won’t backup.
I have a feeling this may be what I need to do - but I don't want to stop backing up photos and videos. If I do add a photo or video folder to the Time Machine exclusion list - will it retain the backups I've made so far? If so, then this will be okay as worst case scenario I can go back and restore from an old backup...

Try BackupLoupe. It shows the files each new backup contains.
Looks interesting. I'll add that to my possibilities...

Try either CarbonCopyCloner or SuperDuper.

Once a day with either should be fine.

And your backups won't continually "grow" in size.
Do these options work similarly to time machine where they don't backup everything? Only what has changed? That is my preference...
 

nambuccaheadsau

macrumors 68000
Oct 19, 2007
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Nambucca Heads Australia
It means use SuperDuper or Carbon CopyCloner.

Either will make an exact copy of your hard dive and it will have the desirable option of being able to boot the machine if there are internal drive problems. I backup weekly, but then if I was still; in business, would follow the fisho's advice.
 

wardie

macrumors 6502
Aug 18, 2008
317
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Create a separate clone with aforementioned products - turn off any archiving of old files options so you get a straight clone not a ‘growing’ one. Then when successful, zap your TM drive and recreate it from scratch. Assumes you have a spare backup drive. I always have one bootable clone and a separate TM anyway.

In reality my only use cases end up being:
- catastrophic main drive failure -> use the bootable copy and off you go!
- mistakenly zapped/edited a file -> go to TM and find suitable old version
 

Fishrrman

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Feb 20, 2009
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"Do these options work similarly to time machine where they don't backup everything? Only what has changed? That is my preference..."

Both CarbonCopyCloner and SuperDuper will do "a full clone" of your source drive the very first time.

After that, they will perform "incremental" backups -- that is, "files that have changed" on the source drive will be copied to the backup (and those only).
Thus, subsequent backups will go much more quickly.

What this means is that the "cloned backup" will always be AN EXACT COPY of the source drive at the last time you backed up. No more, no less.

A cloned backup is FULLY BOOTABLE TO THE FINDER, as well.
You can boot from it and it will look exactly as does your internal drive (again, at the last time you backed up).
You probably won't even be able to tell them apart unless you go to the Apple menu and check "about this Mac".

Both are free to download and try.
 

danielwsmithee

macrumors 65816
Mar 12, 2005
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I have a feeling this may be what I need to do - but I don't want to stop backing up photos and videos. If I do add a photo or video folder to the Time Machine exclusion list - will it retain the backups I've made so far? If so, then this will be okay as worst case scenario I can go back and restore from an old backup...
You just temporarily add it to the exclusion list. It will leave the existing backups in place. Once you figure out which file is corrupt and remove or fix it you remove it from the exclusion list and it picks right back up.
 

Sal Collaziano

macrumors regular
Original poster
Nov 7, 2007
245
7
Royal Palm Beach, FL
Quick update and question...

I installed CarbonCopyCloner and did one full backup. I formatted my Time Machine backup drive and am setting up CCC to handle backups from now on. The only issue I'm having is it appears CCC needs for the Time Machine drive to be mounted continuously - whereas Time Machine would start it up, back up, then dismount it.

Am I doing something wrong? Or do I need to keep the Time Machine drive mounted perpetually? If so, I imagine there's no issue with doing that? But why would Mac OS X dismount it when it's not in use?
 

Fishrrman

macrumors P6
Feb 20, 2009
17,160
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Unless you're doing mission-critical work that must be backed up every hour or so, I'd suggest doing the CCC incremental backups once a day, and be done with it.

If you don't need the backup drive connected "in between", just disconnect it or turn it off.
 

Sal Collaziano

macrumors regular
Original poster
Nov 7, 2007
245
7
Royal Palm Beach, FL
Unless you're doing mission-critical work that must be backed up every hour or so, I'd suggest doing the CCC incremental backups once a day, and be done with it.

If you don't need the backup drive connected "in between", just disconnect it or turn it off.
What I'd like to have is CCC backup my Mac, incrementally, on a daily basis. But it won't do this automatically because the Airport Extreme hard drive is not mounted.

I imagine Time Machine is programmed to automatically mount the drive to perform the backup and unmount it after it's finished. If that's the case, is there a way to set CCC to do the same? Because otherwise, it appears I need to do the backup manually - and my preference is to have backups done while I'm not using the computer...
 

hfg

macrumors 68040
Dec 1, 2006
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Cedar Rapids, IA. USA
What I'd like to have is CCC backup my Mac, incrementally, on a daily basis. But it won't do this automatically because the Airport Extreme hard drive is not mounted.
You might try adding the remote hard drive as a login item. Go to SystemPreferences/Users&Groups/ (your login name) /LoginItems ... then click the "+" button to add and select the disk from the pull-down list.

The drive should appear on your desktop each time you login.
 
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