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Question: Time Machine performs large backup everyday

Since updating to high sierra I've noticed that every day, once a day, my time machine seems to perform a backup of approx 174gb.

Im a litte confused as to why this is happening? Any advice?

iMac, macOS High Sierra (10.13.1)

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Nov 12, 2017 12:32 PM in response to Alastair Riddle In response to Alastair Riddle

Hello Alastair Riddle,

After reviewing your post, it sounds like you are using Time Machine to backup your iMac, but every day it backs up a large file. Time Machine backs up files that were changed. If you have a large file that is edited daily this would happen. I would recommend you read this article, it has more information about how and when Time Machine performs a backup.

Time Machine backs up only the files that changed since the previous backup, so future backups will be faster. ​

How to use Time Machine to back up or restore your Mac

Thank you for using Apple Support Communities. Have a good one.

Nov 12, 2017 12:32 PM

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Nov 12, 2017 12:42 PM in response to brenden dv In response to brenden dv

Thanks for the post. I understand what triggers time

Machine to backup.

So had already ruled that out as a file causing this. No individual files are that big. Only photos and music folders are large. It’s as if maybe a whole folder is getting edited but it never happened before I updated to High Sierra.

I’ve looked for folders that are the same size but to no avail.

Nov 12, 2017 12:42 PM

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Question: Time Machine performs large backup everyday