A question about backing up files

Factual Questions
1

Let’s say I have a bunch of files on my hard drive that were created and/or installed at different periods. They’re presumedly located in the different sections of my hard drive that happened to be available at the time of their modification.

Now say I decide to back-up a bunch of these files on another device. I use a basic drag and drop option.

Do the files get written on to the back-up device in the same order that they exist on the original hard drive? Or does the back-up copy them in a file by file order on to the back-up device?

2

Could you clarify the difference between “the same order they exist on the original hard drive” vs “file by file order”?

What are you trying to accomplish?

3

The files on my hard drive are broken up into pieces and located all over the hard drive. So let’s assume my hard drive looks like this:

A1-A3-G1-D1-B1-D4-E2-E1-F1-G2-D2-A2-B2-C3-C1-C2-D3-F2-E3-H1-H2-G3

Now I tell my computer to move a copy of files A, B, C, D, and E to another drive.

Does my computer just read through my hard drive and copy everything that belongs to those five files as it finds them, in which case my back-up will look like this:

A1-A3-D1-B1-D4-E2-E1-D2-A2-B2-C3-C1-C2-D3-E3

Or does my computer locate the pieces of file A and copy them, then locate the pices of file B and copy them, then locate the pices of file C and copy them, etc. in which case my back-up will look like this:

A1-A2-A3-B1-B2-C1-C2-C3-D1-D2-D3-D4-E1-E2-E3

I’m not really trying to accomplish anything. It works out the same to me. I was just curious.

4

Ahhh, I got it now.
I would assume it would copy them “file by file.” It seems to me that the computer would say “Go get A and put a copy on the other drive” then “Go get B and put a copy on the other drive” etc. Look at it this way. If the new drive is empty, I think it would inherently defrag as it goes.
If you were to clone the drive, I assume it would leave everything in the same order.

5

Assuming you’re doing this at the OS level (e.g. dragging files from one drive to another) they will be copied one file at a time. Of course, the fragmenting, if any, depends on what portions of the target drive are already occupied.

You could also do a direct block copy from one drive to another, but there’s really no good reason to do that unless you’re trying to rescue a corrupt filesystem.

6

Correct in both cases. I have used the copy function to defrag at the same time (on the new drive). A clone copy is track-sector copying without regard to what file the data may be part of.

A clone copy may be faster, since the head movement is limited. A badly fragmented source drive, if used for a file by file copy, can slow the process down significantly since the head movement can be considerable.