Using hard links in Dolphin

[Patrick O'Callaghan]

On Thu, 2009-08-27 at 11:51 -0400, Ben Boeckel wrote:
> [...] 
> > Well sure, but I was hoping to avoid an extra copy stage. Why 
> do you say
> > that copying the files is as fast as linking them? We're 
> talking about a
> > couple of GB here. I agree that copying them to a local 
> directory is not
> > nearly as slow as the backup phase, but it also takes up 
> temporary
> > space. It's just inelegant :-)
> If you use ext4, copy is just as fast as link (still allocates 
> space, but it's copy-on-write, so it's effectively just a link). 
> Only actually does the copy when the data is changed in either.

Where did you read that? I can find no reference to copy-on-write in
ext4. Delayed allocation yes, but that's another matter.

I did a small test:

        $ ls -l Test
        -rw-rw-r-- 1 poc poc 1224693588 2009-08-15 22:14 Test
        $ time ln Test T
        
        real    0m0.022s
        user    0m0.001s
        sys     0m0.001s
        
        $ rm T
        $ time cp Test T
        
        real    1m1.432s
        user    0m0.025s
        sys     0m4.392s
        $

i.e. the copy takes about 20MB/s real time (and I'm not even using
drag-and-drop). This is on a USB external drive with ext4.

> [...]

> > Also, (OT) what's the difference between Play, Queue, Play 
> Next and
> > Queue Next in this menu?
> Amarok? Never seen this menu myself :/ .

Try right-clicking on a media file.

poc