Differentials and deletions

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Differentials and deletions

Postby rseiler » Tue Jun 05, 2018 12:39 pm

This is likely expected, but I'm not sure that I'm on the right track:

I made a full backup of a large data partition, as I've done many times. I then made a differential of it a few days later, as I've done many times.

In the past, the size of the differential that first time (since the full) has been predictably small (0.5GB or so), unless a lot was added. In this case, however, after making the full (not the best timing, I know), but before making the differential, I moved about 60GB of data to a different partition (around 25% of the data overall) to an unrelated partition.

The differential file was as large (3GB) as it tends to be after around a month of routine changes, not a day or two. This must tie to the large number of "changes" made (the deletion of the 60GB), but there was almost no addition in those days, it was almost entirely subtraction.

Am I correct that deletions when it comes to differentials will count against the file size significantly, though clearly not as much as if I had added 60GB? I wonder what would have happened if I'd deleted, say, 90% of the partition. If this follows, the differential file might have been vastly larger than the amount of existing data on the partition, purely due to the number of changes. Perhaps 12GB or so.
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Re: Differentials and deletions

Postby TeraByte Support(PP) » Tue Jun 05, 2018 9:44 pm

File deletions alone don't make that many changes. It could be because of the deletions, though -- going into the Recycle Bin or Previous Versions or even a Windows cleanup/optimization/defrag on the drive.
Paul Purviance
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Re: Differentials and deletions

Postby rseiler » Wed Jun 06, 2018 12:56 pm

This was just a move, which should take the first two things out of play, but maybe because I didn't actually move it off the partition (I misspoke above)? I moved it to a new area, which I excluded via the .ini.
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