ISO FS layout: reducing seeking during read



Hi All,

I’ve backed up much of my harddrive onto DVD+R by arranging my files into 4.5GB directory structures and burning with Roxio EZ CD Creator.

On copying the files back to my harddrive I find that some discs are constantly seeking and so access is very slow. It may only be discs with lots of small files that I have noticed this on. I think I found the using Windows Explorer to drag the files across was slower than using xcopy /e. I’m thinking that Explorer, during it’s Preparing to Copy, generates a sorted list of files to copy and so when it does the copy it is accessing files in a non-optimal order. Perhaps xcopy is not sorting the list, but the order of entries in the DVD’s directory does not exactly correspond to the order of file sectors on the disc.

I’m further assuming that there would be some optimal way of layout out the ISO so that the contents of the files would be accessed sequentially during a read. To do this I guess the directory entries would need to be arranged in the same order as the files are layed out on disc. Even better, perhaps would be if the order of files on disc were in order of filename so that Windows Explorer would just happen to be accessing the files in the correct order.

My question is: have I got this scenario correct (ie. are these concerns with disc layout), and is there some way of getting my files onto a disc in an optimal order so that it’s almost a straightforward sectors after sector read when restoring the backup?

Regards, and thanks in advance.