Original Media, Copied? Linked? Confused.

OK guys I'm quite confused. I did the upgrade to see if it would solve a render problem I was having with 1.0.9 and Mavericks and it seems to have cleared up that problem. However.

I followed the Phil Hodgetts tutorial on updating events/projects. So each of my Event/project is in it's own library. I also saved the old event/projects folder. Now... I see that both the library and the old saved folders have the original media in them... however how can it do this without doubling the amount of data on the HD? I'm thinking that the new library is just pointing to the original media in the old folders. It also said i could delete the old folders and the media would stay in the new libraries...but...I'm very apprehensive to do this.

Your thoughts?

The media is not duplicated. Both the 10.1 library and the old event HD the same media using hard links. If you trash the old events the library will retain the media. You won't recover any drive space. No drive space is list when you make the library and no drive space is gained when you trash the old events.

OK. Thank you Tom. With your good word I'll go ahead and delete.

For those not familiar with hard links, here's a bit more info.

They've been around for ages in Unix, though they're seldom seen on the Mac, partly because there's no GUI interface for creating them. You can create them in the terminal, though, using the 'ln' command.

When you create a file - any file - on disk, the filesystem stores the data, and creates a directory (folder) entry that points to where the data is stored. A hard link is simply an additional directory entry pointing at the same data, and I think I'm right in saying that on most filesystems there is no difference between hard links and original entries - they're the same thing.

The system maintains a 'reference count' for the data, so that when the last link pointing at it is deleted, the data itself is deleted. Deleting a file from a folder doesn't, therefore, necessarily free up the disk space it used. In normal use, it almost always does, because you don't have any extra hard links and so the data only has a reference count of one.

Symbolic links, shortcuts or aliases (’symlinks'), in contrast, are pointers not to the actual data on the disk, but to the directory entry in a folder. One key advantage they have over hard links is that they can span filesystems, so a symlink on your desktop can refer to a file on your server. Hard links to a file must all be on the same disk. But it also means that the original file normally has no knowledge of the symlinks pointing at it - they may be on disks which are offline, for example - so when you delete a file you may later discover that the symlink no longer works (’The original cannot be found').

Symlinks are also very slightly slower, but it's seldom noticeable these days unless you have really large numbers of them. The first time the file is opened through a symlink, the system has to look up the original directory entry and use that to find the data. Hard links point straight at the data. But that typically only saves you a few microseconds the first time you open a file, so it's not normally something to worry about!

Hope that's useful!
Quentin