Macrium Support Forum

Backup size keeps increasing. Why?

By Econdoc - 9 April 2018 9:28 PM

The size of full backups keeps getting larger and larger over time.  I am NOT installing new programs and Windows 10 has not updated in any major way in months. 
Why the increase in backup size?
What can I do to diminish the size of future backups?
By jphughan - 9 April 2018 10:49 PM

First, do you have Synthetic Fulls enabled in your schedule?  If so, I can explain why your Full might be growing each time a consolidation operation occurs when an Incremental runs.

If you're just comparing the initial sizes of brand new Full backups, then check the job logs of your various Full jobs.  You'll see details of each partition included in the job listed under "Operation X of Y", and each of those entries will have a "Used" line item showing how much storage is consumed on that partition.  See which partition(s) are growing with each job.  If you see growth there and you're not sure why, then that's out of scope for Reflect because it just captures images of the partition(s) that you tell it to; you'd have to use some other tool to figure out what files/folders are growing on the partition.  If you're not seeing any meaningful growth there over time, then check the "New File" line item toward the bottom of each job log.  If that's growing even though the amount of source data isn't changing, then that would indicate that even though the total amount of data on the partitions isn't fluctuating much, the nature of the data may be changing such that it is less compressible, in which case the resulting Full file will be larger.
By jphughan - 10 April 2018 3:27 AM

One additional idea.  If your various Full backups do contain more source data (rather than Synthetic Fulls accounting for the image size increase) and you're determined to figure out what's responsible for the growth, here's one option:

- Go to the TreeSize Free website.  Click Download, and you can choose to get the Portable version so you don't have to install it.  Then either install it or extract the zip file.
- In Reflect, find 2 image files with an unexplained size discrepancy, and for each one, click Browse Image, assign a drive letter to the partition of interest, check the "Enable access to restricted folders" box, and click OK.
- Launch two instances of TreeSize Free.  In each one, click Select Directory in the upper-left corner and select the drive letter corresponding to one of your mounted images.  TreeSize will sort folders from largest to smallest and repeat that organization for subfolders as you drill down.  If you put the two TreeSize instances next to each other, it should become apparent rather quickly where the discrepancy lies.
By Econdoc - 10 April 2018 10:43 AM

Thanks for your suggestion. It helped.