You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

M4 Mac mini Incorrect file size

Brand new Mac mini M4 with Sequoia 15.1 is giving me a wrong file size.

For example, I have a blank 500 MB image with 524,288,000 bytes (Zero bytes on disk).

Same file on M1 MacBook Air with Sequoia 15.1, 524,288,000 bytes (524.3 MB on disk).

This is the same file, on my Desktop, which is shared with iCloud.

Am I missing something?

Mac mini, macOS 15.1

Posted on Nov 11, 2024 3:01 PM

Reply
4 replies

Nov 12, 2024 6:34 AM in response to gbrohez

Here are some more tests, never got the same amount on disk!

But all files are opening well (using minivmac)

Is Sequoia using a different method to calculate the space on disk?


M1 Mac mini Original (Monterey)

267 390 976 bytes (267.4 MB on disk)

M4 Mac mini transferred with Migration assistant (Sequoia)

267,390,976 bytes (244.3 MB on disk)

M4 Mac mini manually copied from M1 (Sequoia)

267,390,976 bytes (275 MB on disk)

Nov 14, 2024 6:02 AM in response to gbrohez

This is the type of things that I was suspecting.

 The space on disk is frequently less than the number of bytes due to APFS functionality like compression, clones, sparse files, and extended attributes. Occasionally it is more - copying over a network can contribute to this. The size also depends on the method of copying - from your results, Migration Assistant is better able to make use of APFS optimisation than (and I am guessing what you did) a drag and drop in Finder from a network share.

Thanks to gilby101 for this explanation

https://forums.macrumors.com/threads/incorrect-file-size.2442801/


M4 Mac mini Incorrect file size

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.