Media Set "Use at most" setting not accurate

[amkassir]

I'm trying to create a new disk media set on an empty volume that has 384 GB free space. When I create the media set in Retrospect, if I set the "Use at most" setting to 100%, it shows 100% = 358 GB. For some reason, Retrospect is thinking the available space for the Media Set is significantly smaller than it should be. How can I get Retrospect to take advantage of all the space available? I'm storing the catalog on another volume.

 

Retrospect 10.1

OS 10.8.3

 

Thanks.

[derek500]

Right off the bat I'm thinking that it's the difference between 1000* vs 1024* size reporting. I thought Apple started reporting volume sizes at 1000* recently, maybe Retrospect is still reporting with 1024* sizes.

Sorry if my naming is crude - here's an article that talks about the difference: http://www.howtogeek.com/123268/windows-hard-drive-wrong-capacity/

[amkassir]

I like this MacWorld article...it's simpler and Mac-oriented.

 

Your insightful explanation is exactly right. Apparently, Mountain Lion, Lion, and Snow Leopard all use gigabytes (GB) as 1 GB = 1000 bytes cubed, whereas Retrospect is using the classical gibabytes (GiB), formerly called gigabytes, where 1 GiB = 1024 bytes cubed. if you do the math, the 384 GB reported by the Finder just about exactly equals the 358 GB reported by Retrospect.

 

Thanks!