Yosemite, weird backup size!!!!!!

[macwinpraxis]

Since Yosemite, I am astonished what is wrong with size of backup data. Time machine makes (should make) an incremental backup every hour. But since Yosemite is running on my iMac, the amount of data which is backed up is weird.
During one hour, I may receive a few emails, design a webpage or write something. All together may make 100kB or one or two MB. But the time machine backs up unexpected 20 or 30 GB (and sometimes 2MB)!!!! It hasn't happened just once. I check this regularly and see this strange issue.

Has anybody an Idea why this happens?

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I got the answer from hfg and then from Weaselboy. Thanks guys.

http://kb.parallels.com/en/8827

There is a setting in the newer versions of Parallels to overcome this full backup each time issue.

 

[hfg]

Are you running a Windows virtual machine with Parallels or VMware? That will be included in your TM backup any time you have run Windows and can be 20-30GB each time.

 

[dyt1983]

Time machine makes (should make) an incremental backup every hour.

"Time Machine keeps:
• Local snapshots as space permit
• Hourly backups for the past 24 hours
• Daily backups for the past month
•*Weekly backups for all previous months"

You're forgetting that first line there. If you only want an incremental backup every hour, then you can disable the local snapshots. But remember that if you're using an application that supports the document auto-save and also versions, saving a file several times will result in several versions and possibly more storage requirements.

 

[Weaselboy]

You're forgetting that first line there. If you only want an incremental backup every hour, then you can disable the local snapshots. But remember that if you're using an application that supports the document auto-save and also versions, saving a file several times will result in several versions and possibly more storage requirements.

That's not how local snapshots works. That data gets stored in a hidden /.Mobilebackups folder on the OS drive and does not get copied to the backup drive, so it would not impact the OP's issue.

 

[macwinpraxis]

Are you running a Windows virtual machine with Parallels or VMware? That will be included in your TM backup any time you have run Windows and can be 20-30GB each time.

You may be very right. I do use Parallels and Win7 and Win XP but not so often. I'll keep an eye on it.

 

[Weaselboy]

You may be very right. I do use Parallels and Win7 and Win XP but not so often. I'll keep an eye on it.

http://kb.parallels.com/en/8827

There is a setting in the newer versions of Parallels to overcome this full backup each time issue.

 

[macwinpraxis]

http://kb.parallels.com/en/8827

There is a setting in the newer versions of Parallels to overcome this full backup each time issue.

Thanks a lot. That's it. I use Parallels 10. You are a great help.

 

[dyt1983]

That's not how local snapshots works. That data gets stored in a hidden /.Mobilebackups folder on the OS drive and does not get copied to the backup drive, so it would not impact the OP's issue.

That's correct, sorry but I didn't mean to imply that the actual snapshots get copied. But if you edit and save a single 1MB file several times within an hour, you will clearly see your TM backup size increase over just 1MB. But it would be hard pressed to go up to 20GB.

The setting in Parallels is kind of redundant, it's just easier to exclude the whole VM directory from Time Machine.

 

[Weaselboy]

That's correct, sorry but I didn't mean to imply that the actual snapshots get copied. But if you edit and save a single 1MB file several times within an hour, you will clearly see your TM backup size increase over just 1MB. But it would be hard pressed to go up to 20GB.

Ah... gotcha. The way you mentioned the "first line", I thought you were referring to the local snapshots.

The setting in Parallels is kind of redundant, it's just easier to exclude the whole VM directory from Time Machine.

But then the VM won't be backed up if that is important to you. As I understand that setting it will allow the VM to be backed up incrementally like normal TM data.

 

[dyt1983]

But then the VM won't be backed up if that is important to you. As I understand that setting it will allow the VM to be backed up incrementally like normal TM data.

Oh I see, it wasn't clear to me but now it is. You were referring to the "Smart Guard" and I incorrectly assumed you meant the "Time Machine" setting . The Smart Guard doubles the disk space requirements for just a few snapshots and reduces VM performance, but does give a file that can be incrementally backed up with TM (and is a pain to restore). But still a good suggestion.

Edit: wow, I tried it and each snapshot was about 35-50% of the VDI file. An improvement yes, but still quite large!