Differential backups copy too many files

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Differential backups copy too many files

Post by lundew01 » Wed Jun 12, 2019 2:42 am

I am doing a daily backup from a large directory in my C:\ drive (about 162K files) to two external hard drives.
I have specified "Differential" for the backup type.
The "Reset Archive" option is checked.

In reviewing my daily log, it says over 323K files "Processed" and over 237K files "Backed Up", taking over 4 hours to complete a backup.
Since my task is backing up this directory to two separate external drives, the 323K files" Processed" sounds close to the 2 times 162K files.

I typically change or create files numbering around around 2-5 per day.
So why are so many files being "backed up" each day?
With so few files being changed per day, I would expect the backup to only take "minutes" to complete.

It sort of sounds like the Archive bit is not being checked and all the files might be getting copied.

Any ideas of what to check for in my task setup?

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Re: Differential backups copy too many files

Post by cobian » Wed Jun 12, 2019 11:08 pm

I think you are expecting the behavior of an INCREMENTAL backup. A differential backup will only resent after a full backup.
Luis Cobian
Cobian Backup's creator and Developer

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