Is this normal?

[runplaysleeprun]

I just backed up a few of my apps to my external drive, but they show a different size on the two drives, one is 302.2 MB, and the other 364.1, but I just copied it over.

They both list the same number of bytes, though. Is it due to the different formating of the external drive (FAT32)?

 

[jellomizer]

I would say Yes.
These are different file systems, So they use different methods of storing the Data. They normally group data in fixed size segments, different file systems use different size segments so if you say have a 1k segment vs. a 2k segment. And you have a file that is 1.2k it will actually take up 2k worth of space. So this is normal for the sizes to be a bit differently... And I bet if you copy it back to the same file system they will be the same size agian.

 

[itickings]

They both list the same number of bytes, though. Is it due to the different formating of the external drive (FAT32)?

Yes. FAT32 wasn't really intended for as large drives as we have today.

While it technically supports them (we're nowhere near FAT32's theoretical limits yet), each file will in general waste much more space than modern file systems, and for very small files, the waste will be several times the file's size.

For a more technical explanation, look up "cluster size" or check http://www.pcguide.com/ref/hdd/file/partSlack-c.html for ideas.

 

[runplaysleeprun]

wow, that is a lot of wasted HD space. I only didn't format that drive HFS+ so I could (If I ever needed to) use it with Windows as well. I didn't realize I'd be losing approx. 1/5 of my space to writing inefficiencies.

bummer.

 

[itickings]

wow, that is a lot of wasted HD space. I only didn't format that drive HFS+ so I could (If I ever needed to) use it with Windows as well. I didn't realize I'd be losing approx. 1/5 of my space to writing inefficiencies.

Besides from wasting space, you can't have individual files larger than 4GiB in FAT32, and may run into problems with filenames, permissions and stuff.

So, for small files you will lose lots of space, and for large file, well, you can't have them...